Execute Brain****: Difference between revisions
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<pre>import java.io.IOException;
public class Interpreter {
Line 3,722:
}
}
</pre>
=={{header|JavaScript}}==
|
Revision as of 07:25, 5 January 2021
You are encouraged to solve this task according to the task description, using any language you may know.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly implement the following instructions:
Command | Description |
---|---|
> |
Move the pointer to the right |
< |
Move the pointer to the left |
+ |
Increment the memory cell under the pointer |
- |
Decrement the memory cell under the pointer |
. |
Output the character signified by the cell at the pointer |
, |
Input a character and store it in the cell at the pointer |
[ |
Jump past the matching ] if the cell under the pointer is 0
|
] |
Jump back to the matching [ if the cell under the pointer is nonzero
|
Any cell size is allowed, EOF (End-O-File) support is optional, as is whether you have bounded or unbounded memory.
11l
<lang 11l>F bf(source)
V tape = DefaultDict[Int, Int]() V cell = 0 V ptr = 0 L ptr < source.len S source[ptr] ‘>’ cell++ ‘<’ cell-- ‘+’ tape[cell]++ ‘-’ tape[cell]-- ‘.’ :stdout.write(Char(code' tape[cell])) ‘,’ tape[cell] = :stdin.read(1).code ‘[’ I tape[cell] == 0 V nesting_level = 0 L S source[ptr] ‘[’ nesting_level++ ‘]’ I --nesting_level == 0 L.break ptr++ ‘]’ I tape[cell] != 0 V nesting_level = 0 L S source[ptr] ‘[’ I --nesting_level == 0 L.break ‘]’ nesting_level++ ptr-- ptr++
bf(‘++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.’)</lang>
68000 Assembly
Takes a Brainfuck program as a command line parameter. Escape character (escape key!) is handled as a 0 when inputting characters. Does NOT support break, so programs that don't end by themselves will run forever. <lang 68000devpac>;
- Brainfuck interpreter by Thorham
- 68000+ AmigaOs2+
- Cell size is a byte
incdir "asminc:"
include "dos/dosextens.i" include "lvo/lvos.i"
execBase equ 4
start
- parse command line parameter
move.l a0,fileName
move.b (a0)+,d0 beq exit ; no parameter
cmp.b #'"',d0 ; filter out double quotes bne .loop
addq.l #1,fileName
.loop
move.b (a0)+,d0
cmp.b #'"',d0 ; filter out double quotes beq .done
cmp.b #32,d0 bge .loop
.done
clr.b -(a0) ; end of string
- open dos library
move.l execBase,a6
lea dosName,a1 moveq #36,d0 jsr _LVOOpenLibrary(a6) move.l d0,dosBase beq exit
- get stdin and stdout handles
move.l dosBase,a6
jsr _LVOInput(a6) move.l d0,stdIn beq exit
jsr _LVOOutput(a6) move.l d0,stdOut beq exit
move.l stdIn,d1 jsr _LVOFlush(a6)
- open file
move.l fileName,d1 move.l #MODE_OLDFILE,d2 jsr _LVOOpen(a6) move.l d0,fileHandle beq exit
- examine file
lea fileInfoBlock,a4
move.l fileHandle,d1 move.l a4,d2 jsr _LVOExamineFH(a6) tst.w d0 beq exit
- exit if the file is a folder
tst.l fib_DirEntryType(a4) bge exit
- allocate file memory
move.l execBase,a6
move.l fib_Size(a4),d0 beq exit ; exit if file is empty clr.l d1 jsr _LVOAllocVec(a6) move.l d0,program beq exit
- read file
move.l dosBase,a6
move.l fileHandle,d1 move.l program,d2 move.l fib_Size(a4),d3 jsr _LVORead(a6) tst d0 ble exit ; exit if read didn't succeed
- close file
move.l fileHandle,d1 jsr _LVOClose(a6) clr.l fileHandle
- clear tape (bss section is allocated by os but not cleared)
lea tape,a0 lea tapeEnd,a1
.loopClear
clr.b (a0)+ cmp.l a0,a1 bne .loopClear
- interpreter
move.l program,a2 lea tape,a3
clr.l d2
move.l a2,d6 ; start of program move.l a2,d7 ; end of program add.l fib_Size(a4),d7
loop
move.b (a2)+,d2
cmp.b #">",d2 beq .incPtr
cmp.b #"<",d2 beq .decPtr
cmp.b #"+",d2 beq .incMem
cmp.b #"-",d2 beq .decMem
cmp.b #".",d2 beq .outMem
cmp.b #",",d2 beq .inMem
cmp.b #"[",d2 beq .jmpForward
cmp.b #"]",d2 beq .jmpBack
- next command
.next
cmp.l d7,a2 ; test end of program blt loop
- end of program reached
bra exit
- command implementations
.incPtr
addq.l #1,a3 cmp.l #tapeEnd,a3 ; test end of tape bge exit bra .next
.decPtr
subq.l #1,a3 cmp.l #tape,a3 ; test start of tape blt exit bra .next
.incMem
addq.b #1,(a3) bra .next
.decMem
subq.b #1,(a3) bra .next
.outMem
move.l stdOut,d1 move.b (a3),d2 jsr _LVOFPutC(a6) bra .next
.inMem
move.l stdIn,d1 jsr _LVOFGetC(a6)
cmp.b #27,d0 ; convert escape to 0 bne .notEscape moveq #0,d0
.notEscape
move.b d0,(a3)
bra .next
.jmpForward
tst.b (a3) bne .next
move.l a2,a4 clr.l d3
.loopf
cmp.l d7,a4 ; test end of program bge exit
move.b (a4)+,d2
cmp.b #"[",d2 bne .lf
addq.l #1,d3 bra .loopf
.lf
cmp.b #"]",d2 bne .loopf
subq.l #1,d3 bge .loopf
move.l a4,a2 bra .next
.jmpBack
tst.b (a3) beq .next
move.l a2,a4 clr.l d3
.loopb
move.b -(a4),d2
cmp.l d6,a4 ; test start of program blt exit
cmp.b #"]",d2 bne .lb
addq.l #1,d3 bra .loopb
.lb
cmp.b #"[",d2 bne .loopb
subq.l #1,d3 bgt .loopb
move.l a4,a2 bra .next
- cleanup and exit
exit
move.l dosBase,a6
move.l fileHandle,d1 beq .noFile jsr _LVOClose(a6)
.noFile
move.l execBase,a6
move.l program,a1 tst.l a1 beq .noMem jsr _LVOFreeVec(a6)
.noMem
move.l dosBase,a1 tst.l a1 beq .noLib jsr _LVOCloseLibrary(a6)
.noLib
rts
- data
section data,data_p
dosBase
dc.l 0
fileName
dc.l 0
fileHandle
dc.l 0
fileInfoBlock
dcb.b fib_SIZEOF
stdIn
dc.l 0
stdOut
dc.l 0
program
dc.l 0
dosName
dc.b "dos.library",0
- tape memory
section mem,bss_p
tape
ds.b 1024*64
tapeEnd </lang>
8080 Assembly
In order to allow Brain**** programs to run at a somewhat acceptable speed on 8080-based computers, this program compiles the input to 8080 machine code, which it appends to itself. Contractions and clear loops are optimized. It expects to run under CP/M.
<lang 8080asm> ;;; CP/M Brainfuck compiler/interpreter, with a few optimizations getch: equ 1 ; Read character from console putch: equ 2 ; Print character to console puts: equ 9 ; Print string to console fopen: equ 15 ; Open file fread: equ 20 ; Read from file dmaoff: equ 26 ; Set DMA address fcb: equ 5Ch ; FCB for first command line argument EOFCH: equ -1 ; Value stored on the tape on EOF org 100h jmp start ;;; Print the character on the tape, saving HL (tape location), ;;; and including CR/LF translation. bfout: push h ; Keep tape location mov a,m ; What are we printing? cpi 10 ; Newline? jnz outch ; If not, just print the character. mvi e,13 ; Otherwise, print a carriage return first. mvi c,putch call 5 pop h ; Then get the tape back push h outch: mov e,m ; Print the character in A. mvi c,putch call 5 pop h ; Restore tape location. ret ;;; Read a character and store it on the tape, including CR/LF ;;; translation; ^Z is EOF. bfin: push h ; Keep tape location lda bfeoff ; Have we seen EOF yet? ana a jnz bfeof ; If so, return EOF. mvi c,getch ; Otherwise, read character call 5 cpi 26 ; Was it EOF? jz bfeof ; Then handle EOF. cpi 13 ; Was it CR? (Pressing 'Enter' only gives CR.) jnz bfin_s ; If not, just store the character. mvi c,putch ; Otherwise, output a LF (only CR is echoed as well) mvi e,10 call 5 mvi a,10 ; And then store a LF instead of the CR. bfin_s: pop h ; Restore tape location mov m,a ; Store the character ret bfeof: sta bfeoff ; Set the EOF flag (A is nonzero here) pop h ; Restore tape location mvi m,EOFCH ; Store EOF return value. ret bfeoff: db 0 ; EOF flag, EOF seen if nonzero. ;;; Print mismatched brackets error brkerr: lxi d,ebrk ;;; Print error message under DE and quit err: mvi c,puts ; Print string call 5 rst 0 ; Then quit ;;; Error messages. efile: db 'Cannot read file.$' ebrk: db 'Mismatched brackets.$' ;;; BF characters bfchr: db '+-<>,.[]',26 ;;; Main program start: lhld 6 ; Set stack pointer to highest available address sphl mvi c,fopen ; Try to open the file given on the command line lxi d,fcb call 5 inr a ; A=FF on error, lxi d,efile ; so if we couldn't open the file, say so, and stop jz err ;;; Read file into memory in its entirety lxi d,pgm ; Start of input block: mvi c,dmaoff push d ; Keep current address on stack call 5 ; Set DMA to location of current block mvi c,fread ; Read 128-byte block to that address lxi d,fcb call 5 dcr a ; A=1 = end of file jz fdone inr a ; Otherwise, A<>0 = error lxi d,efile jnz err pop h ; Retrieve DMA address lxi d,128 ; Add 128 (advance to next block) dad d xchg ; Put in DE jmp block ; Go get next block. fdone: pop h ; When done, find next address mvi m,26 ; Write EOF, so file always ends with EOF. ;;; Filter out all the non-BF characters lxi h,pgm ; Output pointer push h ; On stack lxi b,pgm ; Input pointer filter: ldax b ; Get current character inx b ; Look at next char next time lxi h,bfchr ; Test against 9 brainfuck characters (8 + EOF) mvi e,9 filchk: cmp m ; Is it a match? jz filfnd ; Then we found it inx h dcr e jnz filchk jmp filter ; Otherwise, try next character filfnd: pop h ; Get pointer from stack mov m,a ; Store current character inx h ; Move pointer push h ; Store pointer back on stack cpi 26 ; Reached the end? jnz filter ; If not, keep going. ;;; Move the program as high up into memory as possible. lxi h,-1024 ; Keep 1K stack space (allowing 512 levels of nested dad sp ; loops) pop d ; Source pointer in DE (destination in HL) move: ldax d ; Copy backwards dcx d mov m,a dcx h ana a ; Until zero is reached jnz move inx h ; Move pointer to byte after zero inx h ;;; Compile the Brainfuck code into 8080 machine code lxi b,0 ; Push zero on stack (as boundary marker) push b lxi d,pgm ; DE = start of binary area (HL at start of source) compil: mov a,m ; Get source byte cpi '+' ; Plus or minus - change the tape value jz tapval cpi '-' jz tapval cpi '<' ; Left or right - move the tape jz tapmov cpi '>' jz tapmov cpi '.' ; Input and output jz chout cpi ',' jz chin cpi '[' ; Start of loop jz loops cpi ']' ; End of loop jz loope cpi 26 ; EOF? jz cdone inx h ; Anything else is ignored jmp compil ;;; Write code for '+' or '-' (change cell value) tapval: mvi c,0 ; C = change in value necessary tapv_s: mov a,m ; Get current byte cpi '+' ; If plus, jz tapinc ; Then we need to increment cpi '-' ; If minus, jz tapdec ; Then we need to decrement ;;; The effect of the last instructions should be to ;;; change the cell at the tape head by C. ;;; If -3 <= B <= 3, INR M/DCR M are most efficient. ;;; Otherwise, MVI A,NN / ADD M / MOV M,A is most efficient. mov a,c ana a ; Zero? jz compil ; Then we do nothing. cpi 4 ; Larger than 3? jc tapinr ; If not, 'INR M' * C cpi -3 ; Smaller than -3? jnc tapdcr ; Then, 'DCR M' * -C xchg ; Otherwise, use an ADD instruction mvi m,3Eh ; 'MVI A,' inx h mov m,c ; C (all math is mod 256) inx h mvi m,86h ; 'ADD M' inx h mvi m,77h ; 'MOV M,A' inx h xchg jmp compil tapinc: inr c ; '+' means one more inx h ; Check next byte jmp tapv_s tapdec: dcr c ; '-' means one less inx h ; Check next byte jmp tapv_s tapinr: mvi a,34h ; INR M (increment cell) jmp wrbyte tapdcr: mvi a,35h ; DCR M (decrement cell) jmp wrnegc ;;; Write code for '<' or '>' (move tape head) tapmov: lxi b,0 ; BC = change in value necessary tapm_s: mov a,m ; Get current byte cpi '>' ; If right, jz taprgt ; Then we need to move the tape right cpi '<' ; If left, jz taplft ; Then we need to move the tape left ;;; Move the tape by BC. ;;; If -4 <= BC <= 4, INX H/DCX H are most efficient. ;;; Otherwise, LXI B,NNNN / DAD B is most efficient. mov a,b ; Is the displacement zero? ora c jz compil ; Then do nothing mov a,b ; Otherwise, is the high byte 0? ana a jnz tbchi ; If not, it might be FF, but mov a,c ; if so, is low byte <= 4? cpi 5 jc tapinx ; Then we need to write 'INX H' C times xra a ; Otherwise, do it the long way tbchi: inr a ; Is the high byte FF? jnz tapwbc ; If not, we'll have to do it the long way mov a,c ; But if so, is low byte >= -4? cpi -4 jnc tapdcx ; Then we can write 'DCX H' -C times tapwbc: xchg ; Otherwise, use a DAD instruction mvi m,1h ; 'LXI B,' inx h mov m,c ; Low byte inx h mov m,b ; High byte inx h mvi m,9h ; 'DAD B' inx h xchg jmp compil taprgt: inx b ; '>' is one to the right inx h ; Check next byte jmp tapm_s taplft: dcx b ; '<' is one to the left inx h ; Check next byte jmp tapm_s tapinx: mvi a,23h ; INX H (move tape right) jmp wrbyte tapdcx: mvi a,2Bh ; DCX H (move tape left) jmp wrnegc ;;; Write the byte in A, -C times, to [DE++] wrnegc: mov b,a ; Keep A mov a,c ; Negate C cma inr a mov c,a mov a,b ;;; Write the byte in A, C times, to [DE++] wrbyte: stax d inx d dcr c jnz wrbyte jmp compil ;;; Write code to print the current tape value chout: inx h ; We know the cmd is '.', so skip it lxi b,bfout ; Call the output routine jmp wrcall ;;; Write code to read a character and store it on the tape chin: inx h ; We know the cmd is ',', so skip it lxi b,bfin ;;; Write code to CALL the routine with address BC wrcall: xchg mvi m,0CDh ; CALL inx h mov m,c ; Low byte inx h mov m,b ; High byte inx h xchg jmp compil ;;; Write code to start a loop loops: inx h ; We know the first cmd is '[' mov b,h ; Check for '-]' mov c,l ldax b cpi '-' jnz loopsw ; If not '-', it's a real loop inx b ldax b cpi ']' jz lzero ; If ']', we just need to set the cell to 0 ;;; Code for loop: MOV A,M / ANA A / JZ cmd-past-loop loopsw: xchg ; Destination pointer in HL mvi m,7Eh ; MOV A,M inx h mvi m,0A7h ; ANA A inx h mvi m,0CAh ; JZ inx h inx h ; Advance past where the destination will go inx h ; (End of loop will fill it in) push h ; Store the address to jump back to on the stack xchg jmp compil ;;; Code to set a cell to zero in one go: MVI M,0 lzero: inx h ; Move past '-]' inx h xchg ; Destination pointer in HL mvi m,36h ; MVI M, inx h mvi m,0 ; 0 inx h xchg jmp compil ;;; Write code to end a loop: MOV A,M / ANA A / JNZ loop-start loope: inx h ; We know the first cmd is ']' xchg ; Destination pointer in HL mvi m,7Eh ; MOV A,M inx h mvi m,0A7h ; ANA A inx h mvi m,0C2h ; JNZ inx h pop b ; Get loop-start from the stack mov a,b ; If it is 0, we've hit the sentinel, which means ora c ; mismatched brackets jz brkerr mov m,c ; Store loop-start, low byte first, inx h mov m,b ; then high byte. inx h dcx b ; The two bytes before loop-start must be filled in mov a,h ; with the address of the cmd past the loop, high stax b ; byte last, dcx b mov a,l ; then low byte stax b xchg jmp compil ;;; Done: finish the code with a RST 0 to end the program cdone: xchg mvi m,0C7h pop b ; If the brackets are all matched, there should be mov a,b ; a zero on the stack. ora c jnz brkerr ;;; Initialize the tape. The fastest way to fill up memory on the ;;; 8080 is to push values to the stack, so we will fill it up ;;; with zeroes, and position the tape there. ;;; HL contains the top of the program. lxi d,32 ; The Brainfuck program doesn't use the stack, so dad d ; reserving 16 levels for CP/M is more than enough. mov a,l ; Complement the value (almost negation, but low bit cma ; doesn't really matter here) mov l,a mov a,h cma mov h,a dad sp ; Add the current stack pointer, giving bytes to fill ana a ; Zero carry mov a,h ; Divide value by two (we push words) rar mov h,a mov a,l rar mov l,a lxi d,0 ztape: push d ; Zero out the tape (on the stack) dcx h mov a,h ora l jnz ztape dad sp ; HL is now 0, add SP to get tape bottom ;;; The compiled program is stored after this point, so we just ;;; fall through into it. nop ; No-op (sentinel value) pgm: equ $ ; Compiled BF program stored here.</lang>
- Output:
A>type hello.bf ++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++. A>brainfk hello.bf Hello World! A>
8086 Assembly
Like the 8080 version, this program compiles its BF input to 8086 machine code, and then jumps to it. Contractions and clear loops are optimized, and the 8086's memory segmentation is used to provide a circular 64k-cell tape with 8-bit cells.
<lang asm> ;;; MS-DOS Brainf*** interpreter/compiler
cpu 8086
putch: equ 2h ; Print character
puts: equ 9h ; Print string
open: equ 3Dh ; Open file
read: equ 3Fh ; Read from file
exit: equ 4Ch ; Exit to DOS
flags: equ 33h ; Set break flags
CMDLEN: equ 80h ; Address of length of command line argument
CMDARG: equ 81h ; Address of text of command line argument
BRK: equ 1 ; Break flag
EOFCH: equ -1 ; Written to the tape on EOF
section .text
org 100h
;;; See if there is enough memory
mov sp,stack.top ; Move stack inward to free up memory
mov ax,cs ; Get allocated memory size from DOS
dec ax ; (It is at location 3 in the MCB, which
mov es,ax ; is located one paragraph above CS.)
mov ax,[es:3]
mov bx,sp ; The amount of memory the program itself
mov cl,4 ; needs is from CS:0 up to CS:SP in bytes,
shr bx,cl ; shifted right by 4 to give paragraphs;
inc bx ; making sure to round up.
mov bp,cs ; The paragraph right after this is used
add bp,bx ; as the segment base for BF's memory.
sub ax,bx ; Free mem = allocated mem - program mem
cmp ax,128*1024/16 ; We'll require at least 128k bytes
jae mem_ok ; (for two separate code and data segments)
mov dx,err.mem ; If we don't have enough,
jmp error ; give an error message.
;;; Stop on Ctrl+C
mem_ok: mov ax,flags<<8|BRK
mov dl,1
int 21h
;;; See if a command line argument was given
mov bl,[CMDLEN] ; Get length of argument
test bl,bl ; See if it's zero
jnz arg_ok
mov dx,err.usage ; Print usage string if no argument given
jmp error
arg_ok: xor bh,bh
mov [CMDARG+bx],bh ; Terminate the argument string with a zero
mov ax,open<<8 ; Try to open the file for reading
mov dx,CMDARG+1 ; Skip first item (always 1)
int 21h
jnc fileok
mov dx,err.file ; Print file error if it fails
jmp error
fileok: mov di,ax ; Keep file handle in DI
xor si,si ; Keep pointer in SI
mov ds,bp ; Start reading into the memory past our stack
block: mov ah,read ; Read from file
mov bx,di
mov cx,0FFFEh
mov dx,si ; To the place just beyond the last read
int 21h
jnc .rdok
mov dx,err.file ; Read error
jmp error
.rdok: test ax,ax ; If zero bytes read, we're done
jz .done
add si,ax ; Move pointer past read
jnc block ; If there's still room, do another read
mov dx,err.mem ; If we overshot, then give memory error
jmp error
.done: mov [si],byte 0 ; Zero-terminate the data
;;; Filter out all non-BF characters
push ds ; Set ES to DS
pop es
xor si,si ; Source and destination pointer to beginning
xor di,di
filter: lodsb ; Get byte from source
xor bx,bx ; See if byte is BF command
.test: cmp al,[cs:bx+bfchar] ; Test against current character
je .match ; If a match, we found it
inc bx ; If not, try next possible command
cmp bx,8
jbe .test
jmp filter ; If we didn't find it, ignore this character
.match: stosb ; We found it, keep it
test al,al ; If zero, we found the end,
jnz filter ; Otherwise, do next character
;;; Compile the BF source into 8086 machine code
add bp,65536/16 ; Set ES to point to the start of the second
mov es,bp ; 64k (4k paragraphs) that we allocated earlier
xor di,di ; Start at address zero,
push di ; Store a zero on the stack as boundary marker,
mov ax,stop ; At 0000, store a far pointer to the
stosw ; cleanup routine,
mov ax,cs
stosw
mov ax,bfout ; At 0004, store a far pointer to the
stosw ; output routine,
mov ax,cs
stosw
mov ax,bfin ; At 0008, store a far pointer to the
stosw ; input routine,
mov ax,cs
stosw ; Compiled BF code starts at 000C.
xor si,si ; Start at beginning of BF source code
compil: lodsb ; Get current command
.ch: cmp di,-16 ; See if we still have 16 bytes free
jb .fch ; (Loop is 11 bytes, +5 for INT 21h/4Ch at end)
mov dx,err.mem ; If not, we're out of memory
jmp error
.fch: cmp al,'+' ; + and - change the value of the current cell
je tapval
cmp al,'-'
je tapval
cmp al,'>' ; < and > move the tape
je tapmov
cmp al,'<'
je tapmov
cmp al,',' ; I/O
jne .tsout ; Conditional jumps are limited to 128-byte
jmp chin ; displacement
.tsout: cmp al,'.'
jne .tsls
jmp chout
.tsls: cmp al,'[' ; Loops
jne .tsle
jmp loops
.tsle: cmp al,']'
jne .tsend
jmp loope
.tsend: test al,al ; Reached zero?
jnz compil ; If not, next command
jmp cdone ; If so, we're done
;;; Compile a string of +s and -s into an 8086 instruction
tapval: xor cl,cl ; Count up contiguous +s and -s modulo 256
.ch: cmp al,'+'
je .inc
cmp al,'-'
je .dec
test cl,cl ; If zero,
jz compil.ch ; it's a no-op.
mov bl,al ; Otherwise, keep next character
cmp cl,-1 ; If -1, decrement cell
mov ax,0FFEh ; DEC BYTE [BX]
je .wword
cmp cl,1 ; If 1, increment cell
mov ax,07FEh ; INC BYTE [BX]
je .wword
mov ax,0780h ; ADD BYTE [BX],
stosw
mov al,cl ; change to cell
stosb
mov al,bl ; Move next character back into AL
jmp compil.ch ; Compile next command
.inc: inc cl ; Increment cell
lodsb
jmp .ch
.dec: dec cl ; Decrement cell
lodsb
jmp .ch
.wword: stosw ; Write instruction word
mov al,bl ; Move next character back into AL
jmp compil.ch ; Compile next command
;;; Compile a string of s into an 8086 instruction
tapmov: xor cx,cx ; Count up contiguous s modulo 65536
.ch: cmp al,'>'
je .right
cmp al,'<'
je .left
test cx,cx ; Is there any net movement at all?
jnz .move ; If so, generate a move instruction
jmp compil.ch ; But otherwise it's a no-op, ignore it
.move: mov bl,al ; Otherwise, keep next character
cmp cx,4 ; If CX<4, a series of INC BX are best
mov al,43h ; INC BX
jb .wbyte
neg cx
cmp cx,4 ; If -CX<4, a series of DEC BX are best
mov al,4Bh ; DEC BX
jb .wbyte
neg cx
mov ax,0C381h ; ADD BX,
stosw
mov ax,cx ; tape movement
stosw
mov al,bl ; Move next character back into AL
jmp compil.ch ; Compile next command
.left: dec cx ; Left: decrement pointer
lodsb
jmp .ch
.right: inc cx ; Right: increment pointer
lodsb
jmp .ch
.wbyte: rep stosb ; Write AL, CX times.
mov al,bl ; Move next character back into AL
jmp compil.ch ; Compile next command
;;; Compile BF input
chin: mov al,2Eh ; CS segment override
stosb
mov ax,1EFFh ; CALL FAR PTR
stosw
mov ax,8 ; Pointer to input routine at address 8
stosw
jmp compil ; Compile next command
;;; Compile BF output
chout: mov al,2Eh ; CS segment override
stosb
mov ax,1EFFh ; CALL FAR PTR
stosw
mov ax,4 ; Pointer to output routine at address 4
stosw
jmp compil
;;; Compile start of loop
loops: cmp word [si],5D2Dh ; Are the next two characters '-]'?
je .zero ; Then just set the cell to zero
mov ax,078Ah ; Otherwise, write out a real loop
stosw ; ^- MOV AL,[BX]
mov ax,0C084h ; TEST AL,AL
stosw
mov ax,0575h ; JNZ loop-body
stosw
mov al,0B8h ; MOV AX, (simulate absolute near jmp)
stosb
xor ax,ax ; loop-end (we don't know it yet so 0)
stosw
mov ax,0E0FFh ; JMP AX
stosw
push di ; Store addr of loop body on stack
jmp compil ; Compile next command
.zero: mov ax,07C6h ; MOV BYTE [BX],
stosw
xor al,al ; 0
stosb
inc si ; Move past -]
inc si
jmp compil ; Compile next command
;;; Compile end of loop
loope: pop bx ; Retrieve address of loop body from stack
test bx,bx ; If it is zero, we've hit the top of stack
jz .ebrkt ; so the brackets aren't balanced.
mov ax,078Ah ; MOV AL,[BX]
stosw
mov ax,0C084h ; TEST AL,AL
stosw
mov ax,0574h ; JZ loop-end
stosw
mov al,0B8h ; MOV AX, (simulate absolute near jmp)
stosb
mov ax,bx ; loop-start
stosw
mov ax,0E0FFh ; JMP AX
stosw
mov [es:bx-4],di ; Store loop-end in matching loop start code
jmp compil
.ebrkt: mov dx,err.brk
jmp error
;;; Compilation is done.
cdone: mov al,2Eh ; Code to jump to cleanup routine
stosb ; ^- CS segment override
mov ax,2EFFh ; JMP FAR PTR
stosw
pop ax ; Should be zero if all loops closed
stosw
test ax,ax ; Were all loops closed?
jz .lp_ok
mov dx,err.brk ; If not, print error
jmp error
.lp_ok: mov [cs:cp],word 12 ; Make far pointer to start of BF code
mov [cs:cp+2],bp ; (which starts at ES:0C = BP:0C)
mov ax,ds ; Set both DS and ES to BF tape segment
mov es,ax ; (also the initial source segment)
xor ax,ax ; Clear the tape (set all bytes to zero)
mov cx,32768
rep stosw
xor bx,bx ; Tape begins at address 0
xor cx,cx ; No EOF and char buffer is empty
jmp far [cs:cp] ; Jump into the BF code
;;; BF program jumps here to stop the program
stop: mov ax,exit<<8|0 ; Quit to DOS with return code 0
int 21h
;;; Print error message in CS:DX and quit with errorlevel 2
error: push cs ; Set DS to CS
pop ds
mov ah,puts ; Print DS:DX
int 21h
mov ax,exit<<8|2 ; Quit to DOS
int 21h
;;; Output subroutine called by the BF program (far call)
bfout: mov ah,putch ; Prepare to write character
mov dl,[bx] ; Get character from tape
cmp dl,10 ; Is it LF?
jne .wr ; If not, just write it
mov dl,13 ; Otherwise, print CR first,
int 21h
mov dl,10 ; then LF.
.wr: int 21h ; Write character
retf
;;; Input subroutine called by the BF program (far call)
;;; Buffered input with CR/LF translation
;;; Note: this keeps state in registers!
;;; CL = chars left in buffer, CH = set if EOF seen,
;;; SI = buffer pointer, ES = BF data segment
bfin: test ch,ch ; EOF seen?
jnz .r_eof
mov ax,cs ; Set DS to our segment
mov ds,ax
.getch: test cl,cl ; Characters left in buffer?
jnz .retch ; If so, return next character
mov bp,bx ; Keep BF tape pointer
mov ah,read ; Read
xor bx,bx ; From STDIN
mov cx,255 ; Max 255 characters
mov dx,ibuf ; Into the buffer
int 21h
mov bx,bp ; Restore tape pointer
jc .ioerr ; If carry set, I/O error
test ax,ax ; If nothing returned, EOF
jz .s_eof
mov cx,ax ; Otherwise, set character count,
mov si,ibuf ; set buffer pointer back to start,
jmp .getch ; and return first character from buffer.
.s_eof: inc ch ; We've seen EOF now
.r_eof: mov al,EOFCH ; Return EOF
jmp .ret
.retch: lodsb ; Get char from buffer
dec cl ; One fewer character left
cmp al,26 ; ^Z = EOF when reading from keyboard
je .s_eof
cmp al,10 ; If it is LF, ignore it and get another
je .getch
cmp al,13 ; If it is CR, return LF instead
jne .ret
mov al,10
.ret: mov dx,es ; Set DS back to BF's data segment
mov ds,dx
mov [bx],al ; Put character on tape
retf
.ioerr: mov dx,err.io ; Print I/O error and quit
jmp error
section .data
bfchar: db '+-<>,.[]',0
err: ;;; Error messages
.usage: db 'BRAINFK PGM.B',13,10,10,9,'Run the BF program in PGM.B$'
.file: db 'Cannot read file$'
.brk: db 'Mismatched brackets$'
.mem: db 'Out of memory$'
.io: db 'I/O Error$'
section .bss
cp: resw 2 ; Far pointer to start of BF code
ibuf: resb 256 ; 255 char input buffer
stack: resw 512 ; 512 words for the stack
.top: equ $</lang>
- Output:
C:\>type hello.bf ++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++. C:\>brainfk hello.bf Hello World! C:\>
Ada
Agena
Tested with Agena 2.9.5 Win32 <lang agena># Brain**** interpreter
- execute the Brain**** program in the code string
bf := proc( code :: string ) is
local address := 1; # current data address local pc := 1; # current position in code local data := []; # data - initially empty local input := ""; # user input - initially empty local bfOperations := # table of operations and their implemntations [ ">" ~ proc() is inc address, 1 end , "<" ~ proc() is dec address, 1 end , "+" ~ proc() is inc data[ address ], 1 end , "-" ~ proc() is dec data[ address ], 1 end , "." ~ proc() is io.write( char( data[ address ] ) ) end , "," ~ proc() is # get next input character, converted to an integer while input = "" do # no input left - get the next line input := io.read() od; data[ address ] := abs( input[ 1 ] ); # remove the latest character from the input if size input < 2 then input := "" else input := input[ 2 to -1 ] fi end , "[" ~ proc() is if data[ address ] = 0 then # skip to the end of the loop local depth := 0; do inc pc, 1; if code[ pc ] = "[" then inc depth, 1 elif code[ pc ] = "]" then dec depth, 1 fi until depth < 0 fi end , "]" ~ proc() is if data[ address ] <> 0 then # skip to the start of the loop local depth := 0; do dec pc, 1; if code[ pc ] = "[" then dec depth, 1 elif code[ pc ] = "]" then inc depth, 1 fi until depth < 0 fi end ]; # execute the operations - ignore anything invalid while pc <= size code do if data[ address ] = null then data[ address ] := 0 fi; if bfOperations[ code[ pc ] ] <> null then bfOperations[ code[ pc ] ]() fi; inc pc, 1 od
end;
- prompt for Brain**** code and execute it, repeating until an empty code string is entered
scope
local code; do io.write( "BF> " ); code := io.read(); bf( code ) until code = ""
epocs;</lang>
ALGOL 68
AppleScript
Outputs debug in a .txt file similar to that of brainfuck.tk <lang AppleScript> set codeString to text returned of (display dialog "Enter BF code:" buttons "OK" default answer "") set inputString to text returned of (display dialog "Enter input string" buttons "OK" default answer "") set codePointer to 1 set loopPosns to {} set tape to {} set tapePointer to 1 set output to {} set inputPointer to 1 set step to 0
set thePath to (path to desktop as Unicode text) & "log.txt" set debug to (open for access file thePath with write permission)
write (step as string) & " (" & ((codePointer - 1) as string) & "): (The program contains " & ((length of codeString) as string) & " instructions.) " to debug
set step to 1
on betterMod(x, y) -- so -2 mod 256 is 254 instead of -2 local x local y try return -y * (round (x / y) rounding down) + x on error eMsg number eNum error "Can't call betterMod() on " & eMsg number eNum end try end betterMod
repeat while codePointer ≤ length of codeString set theChar to (get character codePointer of codeString)
if (theChar = "+") then repeat while (length of tape < tapePointer) set tape to tape & 0 end repeat set item tapePointer of tape to betterMod(((get item tapePointer of tape) + 1), 256) write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | a[" & ((tapePointer - 1) as string) & "]= " & ((item tapePointer of tape) as string) & " " to debug else if (theChar = "-") then repeat while (length of tape < tapePointer) set tape to tape & 0 end repeat set item tapePointer of tape to betterMod(((get item tapePointer of tape) - 1), 256) write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | a[" & ((tapePointer - 1) as string) & "]= " & ((item tapePointer of tape) as string) & " " to debug else if (theChar = "<") then set tapePointer to tapePointer - 1 write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | array pos. now " & ((tapePointer - 1) as string) & " " to debug
else if (theChar = ">") then set tapePointer to tapePointer + 1 write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | array pos. now " & ((tapePointer - 1) as string) & " " to debug
else if (theChar = "[") then repeat while (length of tape < tapePointer) set tape to tape & 0 end repeat write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | Array[" & ((tapePointer - 1) as string) & "] is '" & ((item tapePointer of tape) as string) & "'" to debug if (item tapePointer of tape ≠ 0) then set loopPosns to loopPosns & codePointer write " ** Loop nesting level: " & (((length of loopPosns) - 1) as string) & ". " to debug else write " " & (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | Not entering a loop but skipping to instruction number " to debug set matchLoops to 1 repeat while matchLoops ≠ 0 set codePointer to codePointer + 1 if (item codePointer of codeString = "[") then set matchLoops to matchLoops + 1 else if (item codePointer of codeString = "]") then set matchLoops to matchLoops - 1 end if end repeat write ((codePointer - 1) as string) & " " to debug end if
else if (theChar = "]") then repeat while (length of tape < tapePointer) set tape to tape & 0 end repeat write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | Array[" & ((tapePointer - 1) as string) & "] is '" & ((item tapePointer of tape) as string) & "' " to debug if (item tapePointer of tape ≠ 0) then write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | looping back to " & (((item (length of loopPosns) of loopPosns) - 1) as string) & " " to debug set codePointer to (item (length of loopPosns) of loopPosns) - 1 end if if (length of loopPosns > 1) then set loopPosns to items 1 thru ((length of loopPosns) - 1) of loopPosns else set loopPosns to {} end if
else if (theChar = ".") then repeat while (length of tape < tapePointer) set tape to tape & 0 end repeat write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | output '" & ((item tapePointer of tape) as string) & "' " & string id (item tapePointer of tape) & " " to debug set output to output & item tapePointer of tape
else if (theChar = ",") then repeat while (length of tape < tapePointer) set tape to tape & 0 end repeat if (inputPointer > length of inputString) then set inputPointer to 1 end if set item tapePointer of tape to id of item inputPointer of inputString set inputPointer to inputPointer + 1 write (step as string) & " (" & ((codePointer - 1) as string) & "): " & (item codePointer of codeString) & " | read in " & string id (item tapePointer of tape) & " (" & ((item tapePointer of tape) as string) & ") " to debug end if
set codePointer to codePointer + 1 set step to step + 1 end repeat
set strout to string id output display dialog strout close access debug </lang>
Arturo
<lang arturo>/*********************************
* Brainf*ck compiler * In Art:uro *********************************/
Tape : #(0) DataPointer : 0 InstructionPointer : 0
// Look for jumps in Code an register them // in the Jumps table
precomputeJumps: {
stack : #() jumphash : #{} instrPointer : 0
loop instrPointer<CodeLength { command: [chars Code].[instrPointer] if command="[" { stack: stack+instrPointer } { if command="]" { target: last stack deleteBy stack [size stack]-1 jumphash.[toString target]: instrPointer jumphash.[toString instrPointer]: target } } instrPointer: instrPointer+1 } jumphash
}
// Check if current state is valid
StateIsValid: -> all #(0<=DataPointer DataPointer<[size Tape] 0<=InstructionPointer InstructionPointer<CodeLength)
// Compile the program
interpret: {
loop [StateIsValid ~] { command: [chars Code].[InstructionPointer] if command="+" -> Tape.[DataPointer]: Tape.[DataPointer]+1 if command="-" -> Tape.[DataPointer]: Tape.[DataPointer]-1 if command=">" { DataPointer: DataPointer+1, if DataPointer=[size Tape] -> Tape: Tape+0 } if command="<" -> DataPointer: DataPointer-1 if command="." -> prints [char Tape.[DataPointer]] if command="," { inp: toNumber|input ~ if inp=13 { inp: 10 } if inp=3 { panic "something went wrong!" } Tape.DataPointer: inp } if command="[" { if Tape.[DataPointer]=0 -> InstructionPointer: Jumps.[toString InstructionPointer] } if command="]" { if Tape.[DataPointer]!=0 -> InstructionPointer: Jumps.[toString InstructionPointer] }
InstructionPointer: InstructionPointer+1 }
}
if [size &]<1 -> panic "Not enough arguments - Usage: bfc <script>"
Code : read &0 CodeLength : size Code Jumps : precomputeJumps ~
interpret ~ </lang>
- Input:
<lang bf>++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.</lang>
- Output:
Hello World!
AutoHotkey
AutoIt
<lang AutoIt>; AutoFucck
- A AutoIt Brainfuck Interpreter
- by minx
- AutoIt Version
- 3.3.8.x
- Commands
- - DEC
- + INC
- [ LOOP START
- ] LOOP END
- . Output cell value as ASCII Chr
- , Input a ASCII char (cell value = ASCII code)
- Ouput cell value as integer
- ; Input a Integer
- _ Output a single whitespace
- / Output an Carriage Return and Line Feed
- You can load & save .atf Files.
- include <WindowsConstants.au3>
- include <EditConstants.au3>
- include <Array.au3>
- include <GUIConstants.au3>
- include <StaticCOnstants.au3>
HotKeySet("{F5}", "_Runn")
$hMain = GUICreate("Autofuck - Real Brainfuck Interpreter", 600, 525) $mMain = GUICtrlCreateMenu("File") Global $mCode = GUICtrlCreateMenu("Code") $mInfo = GUICtrlCreateMenu("Info") $mCredits = GUICtrlCreateMenuItem("Credits", $mInfo) $mFile_New = GUICtrlCreateMenuItem("New", $mMain) $mFile_Open = GUICtrlCreateMenuItem("Open", $mMain) $mFile_Save = GUICtrlCreateMenuItem("Save", $mMain) Global $mCode_Run = GUICtrlCreateMenuItem("Run [F5]", $mCode) Global $lStatus = GUICtrlCreateLabel("++ Autofuck started...", 5, 480, 590, 20, $SS_SUNKEN) GUICtrlSetFont(-1, Default, Default, Default, "Courier New") $eCode = GUICtrlCreateEdit("", 5, 5, 590, 350) GUICtrlSetFont(-1, Default, Default, Default, "Courier New") $eConsole = GUICtrlCreateEdit("", 5, 360, 590, 115, $ES_WANTRETURN) GUICtrlSetFont(-1, Default, Default, Default, "Courier New") GUISetState()
While 1 $nMsg = GUIGetMsg() Switch $nMsg Case $mFile_New GUICtrlSetData($eCode, "") Case $mFile_Open GUICtrlSetData($eCode, FileRead(FileOpenDialog("Open Autofuck script", @DesktopDir, "Autofuck (*.atf)"))) Case $mFile_Save FileWrite(FileOpen(StringReplace(FileSaveDialog("Save Autofuck script", @DesktopDir, "Autofuck (*.atf)"), ".atf", "") &".atf", 2), GUICtrlRead($eCode)) Case $GUI_EVENT_CLOSE Exit Case $mCredits MsgBox(0, "Autofuck", "Copyright by: "&@CRLF&"minx (autoit.de)"&@CRLF&"crashdemons (autoitscript.com)") EndSwitch WEnd
Func _Runn() $Timer = TimerInit() GUICtrlSetData($lStatus, "++ Program started") Global $tData=DllStructCreate('BYTE[65536]') Global $pData=0 GUICtrlSetData($eConsole, "") Local $aError[6]=[,'Unmatched closing bracket during search','Unmatched opening bracket during search','Unexpected closing bracket','Data pointer passed left boundary','Data pointer passed right boundary']
Local $sError= Local $i=_Run(GUICtrlRead($eCode)) If @error>=0 And @error<6 Then $sError=$aError[@error] If StringLen($sError) Then GUICtrlSetData($eConsole, 'ERROR: '&$sError&'.'&@CRLF&'Ending Instruction Pointer: '&($i-1)&@CRLF&'Current Data Pointer: '&$pData)
GUICtrlSetData($lStatus, "++ Program terminated. Runtime: "& Round( TimerDiff($Timer) / 1000, 4) &"s") EndFunc
Func _Run($Code,$iStart=1,$iEnd=0)
If $iEnd<1 Then $iEnd=StringLen($Code) For $i = $iStart to $iEnd Switch StringMid($Code, $i, 1) Case ">" $pData+=1 If $pData=65536 Then Return SetError(5,0,$i) Case "<" $pData-=1 If $pData<0 Then Return SetError(4,0,$i) Case "+" DllStructSetData($tData,1,DllStructGetData($tData,1,$pData+1)+1,$pData+1) Case "-" DllStructSetData($tData,1,DllStructGetData($tData,1,$pData+1)-1,$pData+1) Case ":" GUICtrlSetData($eConsole, GUICtrlRead($eConsole) & (DllStructGetData($tData,1,$pData+1)))
Case "."
GUICtrlSetData($eConsole, GUICtrlRead($eConsole) & Chr(DllStructGetData($tData,1,$pData+1))) Case ";" Local $cIn=StringMid(InputBox('Autofuck','Enter Number'),1) DllStructSetData($tData,1,Number($cIn),$pData+1)
Case ","
Local $cIn=StringMid(InputBox('Autofuck','Enter one ASCII character'),1,1) DllStructSetData($tData,1,Asc($cIn),$pData+1) Case "[" Local $iStartSub=$i Local $iEndSub=_MatchBracket($Code,$i,$iEnd) If @error<>0 Then Return SetError(@error,0,$iEndSub) While DllStructGetData($tData,1,$pData+1)<>0 Local $iRet=_Run($Code,$iStartSub+1,$iEndSub-1) If @error<>0 Then Return SetError(@error,0,$iRet) WEnd $i=$iEndSub Case ']' Return SetError(3,0,$i)
Case "_" GUICtrlSetData($eConsole, GUICtrlRead($eConsole)&" ") Case "/" GUICtrlSetData($eConsole, GUICtrlRead($eConsole)&@CRLF)
EndSwitch Next Return 0
EndFunc
Func _MatchBracket($Code,$iStart=1,$iEnd=0)
If $iEnd<1 Then $iEnd=StringLen($Code) Local $Open=0 For $i=$iStart To $iEnd Switch StringMid($Code,$i,1) Case '[' $Open+=1 Case ']' $Open-=1 If $Open=0 Then Return $i If $Open<0 Then Return SetError(1,0,$i) EndSwitch Next If $Open>0 Then Return SetError(2,0,$i) Return 0
EndFunc</lang>
AWK
Expects the program (not the program file) to be the first argument to the script. Cells don't wrap (trivial if desired) and the code and arena are unbounded.
<lang AWK>BEGIN { bf=ARGV[1]; ARGV[1] = "" compile(bf) execute() }
- Strips non-instructions, builds the jump table.
function compile(s, i,j,k,f) { c = split(s, src, "") j = 0 for(i = 1; i <= c; i++) { if(src[i] ~ /[\-\+\[\]\<\>,\.]/) code[j++] = src[i]
if(src[i] == "[") { marks[j] = 1 } else if(src[i] == "]") { f = 0 for(k = j; k > 0; k--) { if(k in marks) { jump[k-1] = j - 1 jump[j-1] = k - 1 f = 1 delete marks[k] break } } if(!f) { print "Unmatched ]" exit 1 } } } }
function execute( pc,p,i) { pc = p = 0 while(pc in code) { i = code[pc]
if(i == "+") arena[p]++ else if(i == "-") arena[p]-- else if(i == "<") p-- else if(i == ">") p++ else if(i == ".") printf("%c", arena[p]) else if(i == ",") { while(1) { if (goteof) break if (!gotline) { gotline = getline if(!gotline) goteof = 1 if (goteof) break line = $0 } if (line == "") { gotline=0 m[p]=10 break } if (!genord) { for(i=1; i<256; i++) ord[sprintf("%c",i)] = i genord=1 } c = substr(line, 1, 1) line=substr(line, 2) arena[p] = ord[c] break }
} else if((i == "[" && arena[p] == 0) || (i == "]" && arena[p] != 0)) pc = jump[pc] pc++ } } </lang>
- Output:
$ awk -f /tmp/bf.awk '++++++++++[>+>+++>++++>+++++++>++++++++>+++++++++>++++++++++>+++++++++++>++++++++++++<<<<<<<<<-]>>>>+.>>>>+..<.<++++++++.>>>+.<<+.<<<<++++.<++.>>>+++++++.>>>.+++.<+++++++.--------.<<<<<+.<+++.---.' Goodbye, World!
Axe
In this implementation, the array is limited to 768 bytes due to OS constraints. Call BF with pointers to the (null-terminated) program and input.
Note that this implementation has no error checking.
<lang axe>Lbl BF r₁→P r₂→I L₁→D Fill(D,768,0)
While {P}
{P}→C If C='+' {D}++ ElseIf C='-' {D}-- ElseIf C='>' D++ ElseIf C='<' D-- ElseIf C='.' Disp {D}▶Char ElseIf C=',' {I}→{D} I++ ElseIf C='['?{D}=0 NEXT(P)→P ElseIf C=']' PREV(P)→P End P++
End Return
Lbl NEXT r₁++ 1→S While S
If {r₁}='[' S++ ElseIf {r₁}=']' S-- End r₁++
End r₁ Return
Lbl PREV r₁-- 1→S While S
If {r₁}=']' S++ ElseIf {r₁}='[' S-- End r₁--
End r₁ Return</lang>
Example <lang axe>"++++++++++++++++++++++++++++++++[>+>+<<-]>>+++++++++++++++++++++++++<<++++++++++[>>.-<.<-]"→Str1 BF(Str1,0)</lang>
Output
9▪8▪7▪6▪5▪4▪3▪2▪1▪0▪
BASIC
Implementation in BASIC (QuickBasic dialect).
Applesoft BASIC
<lang ApplesoftBasic>0 ON NOT T GOTO 20 : FOR A = T TO L : B = PEEK(S + P) : ON C%(ASC(MID$(C$, A, T))) GOSUB 1, 2, 3, 4, 5, 8, 6, 7 : NEXT A : END 1 P = P + T : ON P < E GOTO 11 : O = 1E99 2 P = P - T : ON P > M GOTO 11 : O = 1E99 3 B = B + T : B = B - (B > U) * B : GOTO 9 4 B = B - T : B = B - (B < 0) * (B - U) : GOTO 9 5 PRINT CHR$(B); : RETURN 6 D = T : ON NOT B GOTO 10 : RETURN 7 D = M : ON NOT NOT B GOTO 10 : RETURN 8 GET B$ : B = LEN(B$) : IF B THEN B = ASC(B$) 9 POKE S + P, B : RETURN 10 FOR K = D TO 0 STEP 0 : A = A + D : K = K + D%(ASC(MID$(C$, A, T))) : NEXT K : RETURN 11 RETURN 20 HIMEM: 38401 21 LOMEM: 8185 22 DIM C%(14999) : CLEAR 23 POKE 105, PEEK(175) 24 POKE 106, PEEK(176) 25 POKE 107, PEEK(175) 26 POKE 108, PEEK(176) 27 POKE 109, PEEK(175) 28 POKE 110, PEEK(176) 29 HIMEM: 8192 30 T = 1 31 M = -1 32 S = 8192 33 E = 30000 34 U = 255 35 DIM C%(255), D%(255) 43 C%(ASC("+")) = 3 44 C%(ASC(",")) = 6 45 C%(ASC("-")) = 4 46 C%(ASC(".")) = 5 60 C%(ASC("<")) = 2 62 C%(ASC(">")) = 1 91 C%(ASC("[")) = 7 92 D%(ASC("[")) = 1 93 C%(ASC("]")) = 8 94 D%(ASC("]")) = -1 95 C$ = "++++++++[>++++[>++>+++>+++>+<<<<-]>+>->+>>+[<]<-]>>.>>---.+++++++..+++.>.<<-.>.+++.------.--------.>+.>++.+++." 98 L = LEN(C$) 99 GOTO</lang>
BaCon
By the author of BaCon, Peter van Eerten. <lang freebasic>REM REM Brainfuck interpreter
REM Get the separate arguments SPLIT ARGUMENT$ BY " " TO arg$ SIZE dim
IF dim < 2 THEN
PRINT "Usage: bf <file>" END
ENDIF
REM Determine size filesize = FILELEN(arg$[1])
REM Get the contents OPEN arg$[1] FOR READING AS bf
REM claim memory txt = MEMORY(filesize)
REM Read file into memory GETBYTE txt FROM bf SIZE filesize
CLOSE FILE bf
REM Initialize work memory mem = MEMORY(30000)
REM This is The Pointer pointing to memory thepointer = 0
REM This is the cursor pointing in the current program cursor = 0
REM Start interpreting program WHILE cursor < filesize DO
command = PEEK(txt + cursor)
SELECT command CASE 62 INCR thepointer
CASE 60 DECR thepointer
CASE 43 POKE mem + thepointer, PEEK(mem + thepointer) + 1
CASE 45 POKE mem + thepointer, PEEK(mem + thepointer) - 1
CASE 46 PRINT CHR$(PEEK(mem + thepointer));
CASE 44 key = GETKEY POKE mem + thepointer, key
CASE 91 jmp = 1 IF ISFALSE(PEEK(mem + thepointer)) THEN REPEAT INCR cursor IF PEEK(txt + cursor) = 91 THEN INCR jmp ELIF PEEK(txt + cursor) = 93 THEN DECR jmp END IF UNTIL PEEK(txt + cursor) = 93 AND NOT(jmp) END IF
CASE 93 jmp = 1 IF ISTRUE(PEEK(mem + thepointer)) THEN REPEAT DECR cursor IF PEEK(txt + cursor) = 93 THEN INCR jmp ELIF PEEK(txt + cursor) = 91 THEN DECR jmp END IF UNTIL PEEK(txt + cursor) = 91 AND NOT(jmp) END IF END SELECT
INCR cursor
WEND</lang>
BBC BASIC
<lang bbcbasic> bf$ = "++++++++[>++++[>++>+++>+++>+<<<<-]>+>->+>>+[<]<-]>>.>" + \
\ ">---.+++++++..+++.>.<<-.>.+++.------.--------.>+.>++.+++." PROCbrainfuck(bf$) END DEF PROCbrainfuck(b$) LOCAL B%, K%, M%, P% DIM M% LOCAL 65535 B% = 1 : REM pointer to string K% = 0 : REM bracket counter P% = 0 : REM pointer to memory FOR B% = 1 TO LEN(b$) CASE MID$(b$,B%,1) OF WHEN "+": M%?P% += 1 WHEN "-": M%?P% -= 1 WHEN ">": P% += 1 WHEN "<": P% -= 1 WHEN ".": VDU M%?P% WHEN ",": M%?P% = GET WHEN "[": IF M%?P% = 0 THEN K% = 1 B% += 1 WHILE K% IF MID$(b$,B%,1) = "[" THEN K% += 1 IF MID$(b$,B%,1) = "]" THEN K% -= 1 B% += 1 ENDWHILE ENDIF WHEN "]": IF M%?P% <> 0 THEN K% = -1 B% -= 1 WHILE K% IF MID$(b$,B%,1) = "[" THEN K% += 1 IF MID$(b$,B%,1) = "]" THEN K% -= 1 B% -= 1 ENDWHILE ENDIF ENDCASE NEXT ENDPROC
</lang>
- Output:
Hello World!
Brainf***
Brain**** in Brain**** Yey! Credits to Frans, NYYRIKKI, Daniel B Cristofani for the code.
Frans:
"I started to think about a BF interpreter written in BF, and because I did not want to write BF code directly, I started with writing a C program that could generate BF code for often used constructs. After some experimentation, I decided to implement a direct execution mode (making use of a define), so that I didn't have to go through the generate-interpret cycle. This resulted in the BF interpreter in BF generation program. If the macro symbol EXECUTE is not defined, this program when executed generates a BF interpreter in BF. This BF interpreter expects as input a BF program terminated with an exclamation mark, followed by the input for the program to be interpreted. I by no means claim that this BF interpreter in BF is the shortest possible. (Actually, NYYRIKKI wrote a much short one and Daniel B. Cristofani an even shorter one.) The BF interpreter in BF (when filtered through a comment remover) looks like:"
<lang brainf***> >>>,[->+>+<<]>>[-<<+>>]>++++[<++++++++>-]<+<[->>+>>+<<<<]>>>>[-<<<<+>> >>]<<<[->>+>+<<<]>>>[-<<<+>>>]<<[>[->+<]<[-]]>[-]>[[-]<<<<->-<[->>+>>+ <<<<]>>>>[-<<<<+>>>>]<<<[->>+>+<<<]>>>[-<<<+>>>]<<[>[->+<]<[-]]>[-]>]< <<<[->>+<<]>[->+<]>[[-]<<<[->+>+<<]>>[-<<+>>]>++++++[<+++++++>-]<+<[-> >>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-]]< [-]>>[[-]<<<<->-<[->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+> >>]<[<[->>+<<]>[-]]<[-]>>]<<<<[->>>+<<<]>[->>+<<]>+>[<->[-]]<[<<<<+>>> >[-]]<<<[->+>+<<]>>[-<<+>>]>+++++[<+++++++++>-]<<[->>>+>+<<<<]>>>>[-<< <<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-]]<[-]>>[[-]<<<<->-<[ ->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-] ]<[-]>>]<<<<[->>>+<<<]>[->>+<<]>+>[<->[-]]<[<<<<++>>>>[-]]<<<[->+>+<<] >>[-<<+>>]>++++++[<++++++++++>-]<<[->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+ >>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-]]<[-]>>[[-]<<<<->-<[->>>+>+<<<<]>>> >[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-]]<[-]>>]<<<<[-> >>+<<<]>[->>+<<]>+>[<->[-]]<[<<<<+++>>>>[-]]<<<[->+>+<<]>>[-<<+>>]>+++ +++[<++++++++++>-]<++<[->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[- <<<+>>>]<[<[->>+<<]>[-]]<[-]>>[[-]<<<<->-<[->>>+>+<<<<]>>>>[-<<<<+>>>> ]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-]]<[-]>>]<<<<[->>>+<<<]>[->> +<<]>+>[<->[-]]<[<<<<++++>>>>[-]]<<<[->+>+<<]>>[-<<+>>]>+++++[<+++++++ ++>-]<+<[->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[-> >+<<]>[-]]<[-]>>[[-]<<<<->-<[->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<< ]>>>[-<<<+>>>]<[<[->>+<<]>[-]]<[-]>>]<<<<[->>>+<<<]>[->>+<<]>+>[<->[-] ]<[<<<<+++++>>>>[-]]<<<[->+>+<<]>>[-<<+>>]>++++[<+++++++++++>-]<<[->>> +>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-]]<[- ]>>[[-]<<<<->-<[->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>> ]<[<[->>+<<]>[-]]<[-]>>]<<<<[->>>+<<<]>[->>+<<]>+>[<->[-]]<[<<<<++++++ >>>>[-]]<<<[->+>+<<]>>[-<<+>>]>+++++++[<+++++++++++++>-]<<[->>>+>+<<<< ]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-]]<[-]>>[[-] <<<<->-<[->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[-> >+<<]>[-]]<[-]>>]<<<<[->>>+<<<]>[->>+<<]>+>[<->[-]]<[<<<<+++++++>>>>[- ]]<<<[->+>+<<]>>[-<<+>>]>+++++++[<+++++++++++++>-]<++<[->>>+>+<<<<]>>> >[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<<]>[-]]<[-]>>[[-]<<<< ->-<[->>>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>>+<<<]>>>[-<<<+>>>]<[<[->>+<< ]>[-]]<[-]>>]<<<<[->>>+<<<]>[->>+<<]>+>[<->[-]]<[<<<<++++++++>>>>[-]]< <<<[->>+>+<<<]>>>[-<<<+>>>]<[<<<[->>>>>>>>>+<+<<<<<<<<]>>>>>>>>[-<<<<< <<<+>>>>>>>>]<<<<<<<[->>>>>>>>>+<<+<<<<<<<]>>>>>>>[-<<<<<<<+>>>>>>>]>[ <[->>>>>+<<<<<]>[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>+>-]>>[-]<[->+<]<<[[-< <<<<+>>>>>]<<<<<-]<<<<<<<<+>[-]>>[-]]<,[->+>+<<]>>[-<<+>>]>++++[<+++++ +++>-]<+<[->>+>>+<<<<]>>>>[-<<<<+>>>>]<<<[->>+>+<<<]>>>[-<<<+>>>]<<[>[ ->+<]<[-]]>[-]>[[-]<<<<->-<[->>+>>+<<<<]>>>>[-<<<<+>>>>]<<<[->>+>+<<<] >>>[-<<<+>>>]<<[>[->+<]<[-]]>[-]>]<<<<[->>+<<]>[->+<]>]<<<<<[-][->>>>> >>>>+<<<<<<+<<<]>>>[-<<<+>>>]>>>>>>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>> +>-]>>[[-<+<+>>]<<[->>+<<]>[-<+>[<->[-]]]<[[-]<[->+>+<<]>>[-<<+>>]<<[[ -<<<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<<-]<<<<<<<<[-]>>>>>>>>>[-<<<<<<<<<+>> >>>>>>>]<<<<<<<<<<[->>>>>>>>>>+<+<<<<<<<<<]>>>>>>>>>[-<<<<<<<<<+>>>>>> >>>]>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>>+>-]>>>+<<<<[[-<<<<<+>>>>>]<<< <<-]<<<<<<<<+[->>>>>>>>>+<<<<<<+<<<]>>>[-<<<+>>>]>>>>>>[<[->>>>>+<<<<< ]>[->>>>>+<<<<<]>>>>+>-][-]]>>[-<+<+>>]<<[->>+<<]>[-[-<+>[<->[-]]]]<[[ -]<[->+>+<<]>>[-<<+>>]<<[[-<<<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<<-]<<<<<<<< [-]>>>>>>>>>[-<<<<<<<<<+>>>>>>>>>]<<<<<<<<<<[->>>>>>>>>>+<+<<<<<<<<<]> >>>>>>>>[-<<<<<<<<<+>>>>>>>>>]>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>>+>-] >>>-<<<<[[-<<<<<+>>>>>]<<<<<-]<<<<<<<<+[->>>>>>>>>+<<<<<<+<<<]>>>[-<<< +>>>]>>>>>>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>>+>-][-]]>>[-<+<+>>]<<[-> >+<<]>[-[-[-<+>[<->[-]]]]]<[[-]<[->+>+<<]>>[-<<+>>]<<[[-<<<<<+>>>>>]>[ -<<<<<+>>>>>]<<<<<<-]<<<<<<<<[-]>>>>>>>>>[-<<<<<<<<<+>>>>>>>>>]<<<<<<< <<<->+[->>>>>>>>>+<<<<<<+<<<]>>>[-<<<+>>>]>>>>>>[<[->>>>>+<<<<<]>[->>> >>+<<<<<]>>>>+>-][-]]>>[-<+<+>>]<<[->>+<<]>[-[-[-[-<+>[<->[-]]]]]]<[[- ]<[->+>+<<]>>[-<<+>>]<<[[-<<<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<<-]<<<<<<<<[ -]>>>>>>>>>[-<<<<<<<<<+>>>>>>>>>]<<<<<<<<<<+>+[->>>>>>>>>+<<<<<<+<<<]> >>[-<<<+>>>]>>>>>>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>>+>-][-]]>>[-<+<+> >]<<[->>+<<]>[-[-[-[-[-<+>[<->[-]]]]]]]<[[-]<[->+>+<<]>>[-<<+>>]<<[[-< <<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<<-]<<<<<<<<[-]>>>>>>>>>[-<<<<<<<<<+>>>> >>>>>]<<<<<<<<<<[->>>>>>>>>>+<+<<<<<<<<<]>>>>>>>>>[-<<<<<<<<<+>>>>>>>> >]>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>>+>-]>>>.<<<<[[-<<<<<+>>>>>]<<<<< -]<<<<<<<<+[->>>>>>>>>+<<<<<<+<<<]>>>[-<<<+>>>]>>>>>>[<[->>>>>+<<<<<]> [->>>>>+<<<<<]>>>>+>-][-]]>>[-<+<+>>]<<[->>+<<]>[-[-[-[-[-[-<+>[<->[-] ]]]]]]]<[[-]<[->+>+<<]>>[-<<+>>]<<[[-<<<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<< -]<<<<<<<<[-]>>>>>>>>>[-<<<<<<<<<+>>>>>>>>>]<<<<<<<<<<[->>>>>>>>>>+<+< <<<<<<<<]>>>>>>>>>[-<<<<<<<<<+>>>>>>>>>]>[<[->>>>>+<<<<<]>[->>>>>+<<<< <]>>>>+>-]>>>,<<<<[[-<<<<<+>>>>>]<<<<<-]<<<<<<<<+[->>>>>>>>>+<<<<<<+<< <]>>>[-<<<+>>>]>>>>>>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>>+>-][-]]>>[-<+ <+>>]<<[->>+<<]>[-[-[-[-[-[-[-<+>[<->[-]]]]]]]]]<[[-]<[->+>+<<]>>[-<<+ >>]<<[[-<<<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<<-]<<<<<<<<[-]>>>>>>>>>[-<<<<< <<<<+>>>>>>>>>]<<<<<<<<<<[->>>>>>>>>>+<+<<<<<<<<<]>>>>>>>>>[-<<<<<<<<< +>>>>>>>>>]>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>>+>-]>>>[-<<<+>+>>]<<[-> >+<<]<<[[-<<<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<<-]>[-<<<<<<+>>>>>>]>+<<<<<< <[>>>>>>>-<<<<<<<[-]]<<<[->>>>>>>>>+<<<<<<+<<<]>>>[-<<<+>>>]>>>>>>[<[- >>>>>+<<<<<]>[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>+>-]>[[-]<+[<[->>>>>+<<<< <]>[->>>>>+<<<<<]>>>>+>>>[->>+<<<+>]<[->+<]>>>[-[-[-[-[-[-[-<<<+>>>[<< <->>>[-]]]]]]]]]<<<[<+>[-]]>[->>+<<<+>]<[->+<]>>>[-[-[-[-[-[-[-[-<<<+> >>[<<<->>>[-]]]]]]]]]]<<<[<->[-]]<]>[-]]<<[->>>>>+<<<<<]>>>>>+>[-]]>>[ -<+<+>>]<<[->>+<<]>[-[-[-[-[-[-[-[-<+>[<->[-]]]]]]]]]]<[[-][-]<[->+>+< <]>>[-<<+>>]<<[[-<<<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<<-]<<<<<<<<[-]>>>>>>> >>[-<<<<<<<<<+>>>>>>>>>]<<<<<<<<<<[->>>>>>>>>>+<+<<<<<<<<<]>>>>>>>>>[- <<<<<<<<<+>>>>>>>>>]>[<[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>>+>-]>>>[-<<<+> +>>]<<[->>+<<]<<[[-<<<<<+>>>>>]>[-<<<<<+>>>>>]<<<<<<-]>[-<<<<<<+>>>>>> ]<<<<<<[->>>>>>>+<<<<<<<]<<<[->>>>>>>>>+<<<<<<+<<<]>>>[-<<<+>>>]>>>>>> [<[->>>>>+<<<<<]>[->>>>>+<<<<<]>[->>>>>+<<<<<]>>>+>-]>[[-]<+[<[-<<<<<+ >>>>>]>[-<<<<<+>>>>>]<<<<<<->>>[->>+<<<+>]<[->+<]>>>[-[-[-[-[-[-[-<<<+ >>>[<<<->>>[-]]]]]]]]]<<<[<->[-]]>[->>+<<<+>]<[->+<]>>>[-[-[-[-[-[-[-[ -<<<+>>>[<<<->>>[-]]]]]]]]]]<<<[<+>[-]]<]>[-]]<<[->>>>>+<<<<<]>>>>>+>[ -]]>>] </lang>
NYYRIKKI:
"Hi,
I saw your Brain**** interpreter for Brain**** and it encouraged me to write my own version of it. I now write to you as I thought, you might be interested about it.
I wanted to write as fast version as possible so I wrote it directly with Brain****. Here is a list of key tricks, that I used to get maximum performance:
- I used loader routine, that removes comments before executing and converts BF code to internal format. In the internal format numbers 1-8 are used for commands and zero is used to terminate execution (code before line split) This is because handling small numbers is much more effective than handling large numbers in BF.
- I used special IF (x)=0 stucture like this: >+<[>-]>[THEN >] to avoid slow byte copying loops. (Command backup etc.)
- I used 3 bytes for each program element to get maximum speed. Using less would have caused program it self get more slow and complex and using more would have slowed down memory seek. For program memory I used 2 bytes for each element.
Data is not transferred between memory and program. In "[" command I only move Z flag. (Value in memory is more likely to be NZ and "0" is faster to move than "1")
This program works same way as yours. Only difference is, that program termination character is ":" instead of "!" No more explaining... here is the code:"
<lang brainf***> >>>+[,>+++++++[<------>-]<[->+>+<<]>>[-<<+>>]<->+<[>-<[-]]>[-<<[-]++++ +>>>>>]<<[->+>+<<]>>[-<<+>>]<-->+<[>-<[-]]>[-<<[-]++++++++>>>>>]<<[->+ >+<<]>>[-<<+>>]<--->+<[>-<[-]]>[-<<[-]++++++>>>>>]<<[->+>+<<]>>[-<<+>> ]<---->+<[>-<[-]]>[-<<[-]+++++++>>>>>]<<[->+>+<<]>>[-<<+>>]++++++[<--- >-]+<[>-<[-]]>[-<<[-]++++>>>>>]<<[->+>+<<]>>[-<<+>>]+++++[<---->-]+<[> -<[-]]>[-<<[-]+++>>>>>]<<[->+>+<<]>>[-<<+>>]+++++++[<------->-]+<[>-<[ -]]>[-<<[-]+>>>>>]<<[->+>+<<]>>[-<<+>>]+++++++[<------->-]<-->+<[>-<[- ]]>[-<<[-]++>>>>>]<++++[<---->-]<]<<<[<<<]>>> [-->+<[>-]>[>]<<++>[-<<<< <+[>-->+<[>-]>[-<<+>>>]<<+>+<[>-]>[-<<->>>]<<+<[-<<<+>>>]<<<]>>>>>]<-> +<[>-]>[>]<<+>[-<->>>[>>>]>[->+>>+<<<]>[-<+>]>>[-[->>+<<]+>>]+>[->+<]> [-<+>>>[-]+<<]+>>[-<<->>]<<<<[->>[-<<+>>]<<<<]>>[-<<<<<+>>>>>]<<<<<<<[ >>[-<<<+>>>]<<<<<]+>>[>-->+<[>-]>[-<<->>>]<<+>+<[>-]>[-<<+>>>]<<+<[->> >+<<<]>>>]<]<--->+<[>-]>[->>[>>>]>+<<<<[<<<]>>]<<->+<[>-]>[->>[>>>]>-< <<<[<<<]>>]<<->+<[>-]>[->>[>>>]>[->+>>+<<<]>[-<+>]>>[-[->>+<<]+>>]+>+< [-<<]<<<<<[<<<]>>]<<->+<[>-]>[->>[>>>]>[->+>>+<<<]>[-<+>]>>[-[->>+<<]+ >>]+>-<[-<<]<<<<<[<<<]>>]<<->+<[>-]>[->>[>>>]>[->+>>+<<<]>[-<+>]>>[-[- >>+<<]+>>]+>.<[-<<]<<<<<[<<<]>>]<<->+<[>-]>[->>[>>>]>[->+>>+<<<]>[-<+> ]>>[-[->>+<<]+>>]+>,<[-<<]<<<<<[<<<]>>]<<++++++++>>>] </lang>
Daniel B. Cristofani
<lang brainf***>
>>>+[[-]>>[-]++>+>+++++++[<++++>>++<-]++>>+>+>+++++[>++>++++++<<-]+>>>,<++[[>[ ->>]<[>>]<<-]<[<]<+>>[>]>[<+>-[[<+>-]>]<[[[-]<]++<-[<+++++++++>[<->-]>>]>>]]<< ]<]<[[<]>[[>]>>[>>]+[<<]<[<]<+>>-]>[>]+[->>]<<<<[[<<]<[<]+<<[+>+<<-[>-->+<<-[> +<[>>+<<-]]]>[<+>-]<]++>>-->[>]>>[>>]]<<[>>+<[[<]<]>[[<<]<[<]+[-<+>>-[<<+>++>- [<->[<<+>>-]]]<[>+<-]>]>[>]>]>[>>]>>]<<[>>+>>+>>]<<[->>>>>>>>]<<[>.>>>>>>>]<<[ >->>>>>]<<[>,>>>]<<[>+>]<<[+<<]<] [input a brain**** program and its input, separated by an exclamation point. Daniel B Cristofani (cristofdathevanetdotcom) http://www.hevanet.com/cristofd/brainfuck/]
</lang>
Links: [[1]]
[[2]]
[[3]]
Franco C. Bartolabac, a 12 y/o boi.
Brat
Burlesque
<lang burlesque> ".""X"r~"-""\/^^{vvvv}c!!!-.256.%{vvvv}c!sa\/"r~"+""\/^^{vvvv}c!!!+. 256.%{vvvv}c!sa\/"r~"[""{"r~"]""}{\/^^{vvvv}c!!!}w!"r~">""+."r~"<"" -."r~"X""\/^^{vvvv}c!!!L[+]\/+]\/+]^^3\/.+1RAp^\/+]\/[-1RA^^-]\/[-\/ "r~"\'\'1 128r@{vv0}m[0"\/.+pse!vvvv<-sh </lang>
However, this implementation does not support input. Also, output is visible only after the brainfuck program terminated. This is due to the limitation that Burlesque does not have actual I/O.
C
C#
C++
Clojure
<lang clojure>(ns brainfuck)
(def ^:dynamic *input*)
(def ^:dynamic *output*)
(defrecord Data [ptr cells])
(defn inc-ptr [next-cmd]
(fn [data] (next-cmd (update-in data [:ptr] inc))))
(defn dec-ptr [next-cmd]
(fn [data] (next-cmd (update-in data [:ptr] dec))))
(defn inc-cell [next-cmd]
(fn [data] (next-cmd (update-in data [:cells (:ptr data)] (fnil inc 0)))))
(defn dec-cell [next-cmd]
(fn [data] (next-cmd (update-in data [:cells (:ptr data)] (fnil dec 0)))))
(defn output-cell [next-cmd]
(fn [data] (set! *output* (conj *output* (get (:cells data) (:ptr data) 0))) (next-cmd data)))
(defn input-cell [next-cmd]
(fn [data] (let [[input & rest-input] *input*] (set! *input* rest-input) (next-cmd (update-in data [:cells (:ptr data)] input)))))
(defn if-loop [next-cmd loop-cmd]
(fn [data] (next-cmd (loop [d data] (if (zero? (get (:cells d) (:ptr d) 0)) d (recur (loop-cmd d)))))))
(defn terminate [data] data)
(defn split-cmds [cmds]
(letfn [(split [[cmd & rest-cmds] loop-cmds] (when (nil? cmd) (throw (Exception. "invalid commands: missing ]"))) (case cmd \[ (let [[c l] (split-cmds rest-cmds)] (recur c (str loop-cmds "[" l "]"))) \] [(apply str rest-cmds) loop-cmds] (recur rest-cmds (str loop-cmds cmd))))] (split cmds "")))
(defn compile-cmds cmd & rest-cmds
(if (nil? cmd) terminate (case cmd \> (inc-ptr (compile-cmds rest-cmds)) \< (dec-ptr (compile-cmds rest-cmds)) \+ (inc-cell (compile-cmds rest-cmds)) \- (dec-cell (compile-cmds rest-cmds)) \. (output-cell (compile-cmds rest-cmds)) \, (input-cell (compile-cmds rest-cmds)) \[ (let [[cmds loop-cmds] (split-cmds rest-cmds)] (if-loop (compile-cmds cmds) (compile-cmds loop-cmds))) \] (throw (Exception. "invalid commands: missing [")) (compile-cmds rest-cmds))))
(defn compile-and-run [cmds input]
(binding [*input* input *output* []] (let [compiled-cmds (compile-cmds cmds)] (println (compiled-cmds (Data. 0 {})))) (println *output*) (println (apply str (map char *output*)))))
</lang> <lang clojure>brainfuck> (compile-and-run "++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>." []) {:ptr 4, :cells {4 10, 3 33, 2 100, 1 87, 0 0}} [72 101 108 108 111 32 87 111 114 108 100 33 10] Hello World!
nil </lang>
The alternate implementation at Execute Brain****/Clojure showcases a rather different approach.
COBOL
Comefrom0x10
This interpreter takes a command line argument with the path to a Brain**** program. It uses strings as storage, so storage is unbounded on both sides of the pointer, but behavior is undefined for cell values lower than zero or higher than 0x10ffff.
<lang cf0x10>pointer_alpha = 1/0 pointer_numeric = 1/0 tape_behind = tape_ahead = 1/0 tape_pos = 0 # only for debugging array_behind = 1/0 array_ahead = set_tape_ahead = array_ahead array_ahead = 1/0
shift
comefrom if array_ahead is array_ahead cdr = 1/0 cdr = array_ahead shift_tail = cdr new_cell comefrom shift if shift_tail is itoa = 0 shift_tail = itoa car = 1/0 car = array_ahead array_behind = car array_behind done = shift_tail array_ahead = shift_tail comefrom shift if array_ahead is done
set_pointer_alpha = 1/0 set_pointer_alpha
comefrom if set_pointer_alpha atoi = set_pointer_alpha cdr = tape_ahead set_tape_ahead = set_pointer_alpha cdr set_pointer_alpha = 1/0
set_tape_ahead = 1/0 set_pointer_vals
comefrom if set_tape_ahead tape_ahead = set_tape_ahead car = tape_ahead pointer_alpha = car atoi = pointer_alpha pointer_numeric = atoi set_tape_ahead = 1/0
pointer_change = 1/0 change_pointer_val
comefrom if pointer_change car = tape_ahead cdr = tape_ahead itoa = pointer_numeric + pointer_change set_tape_ahead = itoa cdr pointer_change = 1/0
file = 0 # initialize to something other than undefined so jump from file works when read fails read_path = argv error_reading_program
comefrom file if file + 0 is 0 'Error: cannot read Brainfuck program at "' read_path '"'
program_loaded
comefrom file if file is file program_behind = program_ahead = file
run comefrom program_loaded opcode = 1/0 opcode_numeric = 1/0 in_buffer = # cf0x10 stdin is line-buffered jumping = 0 moving = 1 comefrom run
comefrom execute if opcode_numeric is 0 execute comefrom run if moving # can be useful for debugging: #program_ahead moving ':' jumping '@' tape_pos ':' pointer_numeric car = program_ahead atoi = car opcode_numeric = atoi opcode = car opcode = 1/0
#
program_forward comefrom execute if moving > 0 array_behind = program_behind array_ahead = 1/0 array_ahead = program_ahead program_behind = array_behind program_ahead = array_ahead
forward_jump comefrom execute if opcode is '['
jump comefrom forward_jump if pointer_numeric is 0 jumping = jumping + 1 moving = 1 match_brace comefrom forward_jump if jumping < 0 jumping = jumping + 1 stop_jump comefrom match_brace if jumping is 0 moving = 1
program_backward comefrom execute if moving < 0 array_behind = program_ahead array_ahead = 1/0 array_ahead = program_behind program_behind = array_ahead program_ahead = array_behind
backward_jump comefrom execute if opcode is ']'
jump comefrom backward_jump if pointer_numeric > 0 jumping = jumping - 1 moving = -1 match_brace comefrom backward_jump if jumping > 0 jumping = jumping - 1 stop_jump comefrom match_brace if jumping is 0 moving = 1
op comefrom execute if opcode
moving = 1 do_op = opcode comefrom op if jumping # forward comefrom op if do_op is '>' tape_pos = tape_pos + 1 array_ahead = 1/0 array_behind = tape_behind array_ahead = tape_ahead tape_behind = array_behind set_tape_ahead = array_ahead backward comefrom op if do_op is '<' tape_pos = tape_pos - 1 array_ahead = 1/0 array_behind = tape_ahead array_ahead = tape_behind tape_behind = array_ahead set_tape_ahead = array_behind
increment comefrom op if do_op is '+' pointer_change = 1 decrement comefrom op if do_op is '-' pointer_change = -1
print comefrom op if do_op is '.' pointer_alpha... read comefrom op if do_op is ',' # cdr = 1/0 cdr = in_buffer car = in_buffer set_pointer_alpha = car cdr = in_buffer in_buffer = cdr comefrom stdin if stdin + 0 is 0 # block_for_input comefrom read if cdr is stdin = in_buffer = stdin cdr = in_buffer comefrom stdin if stdin + 0 is 0</lang>
Common Lisp
Implementation in Common Lisp.
D
Delphi
Fix of #Pascal to run in Delphi. <lang Delphi> program Execute_Brain;
{$APPTYPE CONSOLE}
uses
Winapi.Windows, System.SysUtils;
const
DataSize = 1024; // Size of Data segment MaxNest = 1000; // Maximum nesting depth of []
function Readkey: Char; var
InputRec: TInputRecord; NumRead: Cardinal; KeyMode: DWORD; StdIn: THandle;
begin
StdIn := GetStdHandle(STD_INPUT_HANDLE); GetConsoleMode(StdIn, KeyMode); SetConsoleMode(StdIn, 0);
repeat ReadConsoleInput(StdIn, InputRec, 1, NumRead); if (InputRec.EventType and KEY_EVENT <> 0) and InputRec.Event.KeyEvent.bKeyDown then begin if InputRec.Event.KeyEvent.AsciiChar <> #0 then begin Result := InputRec.Event.KeyEvent.UnicodeChar; Break; end; end; until FALSE;
SetConsoleMode(StdIn, KeyMode);
end;
procedure ExecuteBF(Source: string); var
Dp: pByte; // Used as the Data Pointer DataSeg: Pointer; // Start of the DataSegment (Cell 0) Ip: pChar; // Used as instruction Pointer LastIp: Pointer; // Last adr of code. JmpStack: array[0..MaxNest - 1] of pChar; // Stack to Keep track of active "[" locations JmpPnt: Integer; // Stack pointer ^^ JmpCnt: Word; // Used to count brackets when skipping forward.
begin
// Set up then data segment getmem(DataSeg, dataSize); Dp := DataSeg;
// fillbyte(dp^,dataSize,0);
FillChar(Dp^, DataSize, 0);
// Set up the JmpStack JmpPnt := -1;
// Set up Instruction Pointer Ip := @Source[1]; LastIp := @Source[length(Source)]; if Ip = nil then exit;
// Main Execution loop repeat { until Ip > LastIp } case Ip^ of '<': dec(Dp); '>': inc(Dp); '+': inc(Dp^); '-': dec(Dp^); '.': write(chr(Dp^)); ',': Dp^ := ord(ReadKey); '[': if Dp^ = 0 then begin // skip forward until matching bracket; JmpCnt := 1; while (JmpCnt > 0) and (Ip <= LastIp) do begin inc(Ip); case Ip^ of '[': inc(JmpCnt); ']': dec(JmpCnt); #0: begin Writeln('Error brackets dont match'); halt; end; end; end; end else begin // Add location to Jump stack inc(JmpPnt); JmpStack[JmpPnt] := Ip; end; ']': if Dp^ > 0 then // Jump Back to matching [ Ip := JmpStack[JmpPnt] else // Remove Jump from stack dec(JmpPnt); end; inc(Ip); until Ip > LastIp; freemem(DataSeg, dataSize);
end;
const
HelloWorldWiki = '++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>' + '---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.'; pressESCtoCont = '>[-]+++++++[<++++++++++>-]<->>[-]+++++++[<+++++++++++' + '+>-]<->>[-]++++[<++++++++>-]+>[-]++++++++++[<++++++++' + '++>-]>[-]++++++++[<++++++++++++++>-]<.++.+<.>..<<.<<.' + '-->.<.>>.>>+.-----.<<.[<<+>>-]<<.>>>>.-.++++++.<++++.' + '+++++.>+.<<<<++.>+[>+<--]>++++...'; waitForEsc = '[-]>[-]++++[<+++++++>-]<->[-]>+[[-]<<[>+>+<<-]' + '>>[<' + '<+>>-],<[->-<]>]';
begin
// Execute "Hello World" example from Wikipedia ExecuteBF(HelloWorldWiki);
// Print text "press ESC to continue....." and wait for ESC to be pressed ExecuteBF(pressESCtoCont + waitForEsc);
end.</lang>
dodo0
<lang dodo0>#Import some functions clojure('count', 1) -> size clojure('nth', 2) -> charAt clojure('inc', 1) -> inc clojure('dec', 1) -> dec clojure('char', 1) -> char clojure('int', 1) -> int clojure('read-line', 0) -> readLine
- The characters we will need
charAt("\n", 0) -> newLine charAt("@", 0) -> exitCommand charAt("+", 0) -> incrCommand charAt("-", 0) -> decrCommand charAt("<", 0) -> shlCommand charAt(">", 0) -> shrCommand charAt(".", 0) -> printCommand charAt(",", 0) -> inputCommand charAt("[", 0) -> repeatCommand charAt("]", 0) -> endCommand
- Read a character from a line of input.
fun readChar -> return ( readLine() -> line size(line) -> length
#Return the ith character and a continuation fun nextFromLine -> i, return ( '='(i, length) -> eol if (eol) -> ( return(newLine, readChar) #end of line ) | charAt(line, i) -> value inc(i) -> i fun next (-> return) nextFromLine(i, return) | next return(value, next) ) | nextFromLine
nextFromLine(0, return) #first character (position 0) ) | readChar
- Define a buffer as a value and a left and right stack
fun empty (-> return, throw) throw("Error: out of bounds") | empty fun fill (-> return, throw) return(0, fill) | fill
fun makeBuffer -> value, left, right, return ( fun buffer (-> return) return(value, left, right) | buffer return(buffer) ) | makeBuffer
fun push -> value, stack, return ( fun newStack (-> return, throw) return(value, stack) | newStack return(newStack) ) | push
- Brainf*** operations
fun noop -> buffer, input, return ( return(buffer, input) ) | noop
fun selectOp -> command, return ( '='(command, incrCommand) -> eq if (eq) -> ( fun increment -> buffer, input, return ( buffer() -> value, left, right inc(value) -> value makeBuffer(value, left, right) -> buffer return(buffer, input) ) | increment return(increment) ) | '='(command, decrCommand) -> eq if (eq) -> ( fun decrement -> buffer, input, return ( buffer() -> value, left, right dec(value) -> value makeBuffer(value, left, right) -> buffer return(buffer, input) ) | decrement return(decrement) ) | '='(command, shlCommand) -> eq if (eq) -> ( fun shiftLeft -> buffer, input, return ( buffer() -> value, left, right push(value, right) -> right left() -> value, left ( makeBuffer(value, left, right) -> buffer return(buffer, input) ) | message println(message) -> exit() ) | shiftLeft return(shiftLeft) ) | '='(command, shrCommand) -> eq if (eq) -> ( fun shiftRight -> buffer, input, return ( buffer() -> value, left, right push(value, left) -> left right() -> value, right ( makeBuffer(value, left, right) -> buffer return(buffer, input) ) | message println(message) -> exit() ) | shiftRight return(shiftRight) ) | '='(command, printCommand) -> eq if (eq) -> ( fun putChar -> buffer, input, return ( buffer() -> value, left, right char(value) -> value 'print'(value) -> dummy 'flush'() -> dummy return(buffer, input) ) | putChar return(putChar) ) | '='(command, inputCommand) -> eq if (eq) -> ( fun getChar -> buffer, input, return ( input() -> letter, input int(letter) -> letter buffer() -> value, left, right makeBuffer(letter, left, right) -> buffer return(buffer, input) ) | getChar return(getChar) ) | return(noop) ) | selectOp
- Repeat until zero operation
fun whileLoop -> buffer, input, continue, break ( buffer() -> value, left, right '='(value, 0) -> zero if (zero) -> ( break(buffer, input) ) | continue(buffer, input) -> buffer, input whileLoop(buffer, input, continue, break) ) | whileLoop
- Convert the Brainf*** program into dodo0 instructions
fun compile -> input, endmark, return ( input() -> command, input
'='(command, endmark) -> eq if (eq) -> ( return(noop, input) #the end, stop compiling ) | #Put in sequence the current operation and the rest of the program fun chainOp -> op, input, return ( compile(input, endmark) -> program, input fun exec -> buffer, input, return ( op(buffer, input) -> buffer, input program(buffer, input, return) ) | exec return(exec, input) ) | chainOp
'='(command, repeatCommand) -> eq if (eq) -> ( compile(input, endCommand) -> body, input #compile until "]"
#Repeat the loop body until zero fun repeat -> buffer, input, return ( whileLoop(buffer, input, body, return) ) | repeat chainOp(repeat, input, return) ) | selectOp(command) -> op chainOp(op, input, return) ) | compile
- Main program
compile(readChar, exitCommand) -> program, input makeBuffer(0, empty, fill) -> buffer input() -> nl, input #consume newline from input
- Execute the program instructions
program(buffer, input) -> buffer, input exit()</lang> Execution:
$ java -classpath antlr-3.2.jar:clojure-1.2.0/clojure.jar:. clojure.main dodo/runner.clj bfc2.do0 ++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.@ Hello World!
E
Elena
Erlang
F#
Factor
Factor comes with a Brainf*** interpreter. See the implementation here.
<lang factor>USE: brainf***
"++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++." run-brainf***</lang>
- Output:
Hello World!
Forth
Fortran
Initial puzzlement as to the nature of the scratchpad was resolved: the source code being interpreted is in one storage area and the data scratchpad is another. Thus, self-modifying code is not in fact possible, so higher level of brain**** is precluded - as are still further opportunities offered by having the instruction and data pointers being in the data scratchpad rather than as separate items. Later experimentation showed that the initial value of all the STORE cells must be zero. Having a specified example code to try would help too.
Interpreter
The source employs F90 so as to gain the convenience of a service routine SEEK contained within RUN that thereby has access to the PROG and the instruction pointer - though these could have been passed as additional parameters. The main idea is that the expression can fit on one line and special code is not used for the two cases. The STORE array of cells is represented as an array of CHARACTER*1 variables rather than a CHARACTER*n single variable. This means that an element is addressed as STORE(i), rather than STORE(i:i), and that STORE = CHAR(0) initialises the whole array to zero. If it were CHARACTER*n, then only the first character would be zero, all subsequent would be blanks. It is not clear what size a cell represents, but a single character suffices for the trial run. For usage that involves arithmetic, the ICHAR and CHAR functions are needed which work on values of 0:255. The cell array could be declared INTEGER*1 instead, which would allow arithmetic without sacrifices on the altar of type checking. Such a variable in two's complement has values of -128:127 however with only addition and subtraction supported this doesn't matter - the bit patterns are the same as for unsigned integers. Larger integer sizes are possible if required, but would require changes to the READ and WRITE statements because A1 format works at the high-order end of a multi-byte variable.
The PROG variable could also be regarded as an array of single characters, but such an array is not a suitable candidate for a text literal such as initialises HELLOWORLD.<lang Fortran> MODULE BRAIN !It will suffer.
INTEGER MSG,KBD CONTAINS !A twisted interpreter. SUBROUTINE RUN(PROG,STORE) !Code and data are separate! CHARACTER*(*) PROG !So, this is the code. CHARACTER*(1) STORE(:) !And this a work area. CHARACTER*1 C !The code of the moment. INTEGER I,D !Fingers to an instruction, and to data. D = 1 !First element of the store. I = 1 !First element of the prog.
DO WHILE(I.LE.LEN(PROG)) !Off the end yet? C = PROG(I:I) !Load the opcode fingered by I. I = I + 1 !Advance one. The classic. SELECT CASE(C) !Now decode the instruction. CASE(">"); D = D + 1 !Move the data finger one place right. CASE("<"); D = D - 1 !Move the data finger one place left. CASE("+"); STORE(D) = CHAR(ICHAR(STORE(D)) + 1) !Add one to the fingered datum. CASE("-"); STORE(D) = CHAR(ICHAR(STORE(D)) - 1) !Subtract one. CASE("."); WRITE (MSG,1) STORE(D) !Write a character. CASE(","); READ (KBD,1) STORE(D) !Read a character. CASE("["); IF (ICHAR(STORE(D)).EQ.0) CALL SEEK(+1) !Conditionally, surge forward. CASE("]"); IF (ICHAR(STORE(D)).NE.0) CALL SEEK(-1) !Conditionally, retreat. CASE DEFAULT !For all others,
!Do nothing.
END SELECT !That was simple. END DO !See what comes next.
1 FORMAT (A1,$) !One character, no advance to the next line. CONTAINS !Now for an assistant. SUBROUTINE SEEK(WAY) !Look for the BA that matches the AB. INTEGER WAY !Which direction: ±1. CHARACTER*1 AB,BA !The dancers. INTEGER INDEEP !Nested brackets are allowed. INDEEP = 0 !None have been counted. I = I - 1 !Back to where C came from PROG. AB = PROG(I:I) !The starter. BA = "[ ]"(WAY + 2:WAY + 2) !The stopper. 1 IF (I.GT.LEN(PROG)) STOP "Out of code!" !Perhaps not! IF (PROG(I:I).EQ.AB) THEN !A starter? (Even if backwards) INDEEP = INDEEP + 1 !Yep. ELSE IF (PROG(I:I).EQ.BA) THEN !A stopper? INDEEP = INDEEP - 1 !Yep. END IF !A case statement requires constants. IF (INDEEP.GT.0) THEN !Are we out of it yet? I = I + WAY !No. Move. IF (I.GT.0) GO TO 1 !And try again. STOP "Back to 0!" !Perhaps not. END IF !But if we are out of the nest, I = I + 1 !Advance to the following instruction, either WAY. END SUBROUTINE SEEK !Seek, and one shall surely find. END SUBROUTINE RUN !So much for that. END MODULE BRAIN !Simple in itself.
PROGRAM POKE !A tester. USE BRAIN !In a rather bad way. CHARACTER*1 STORE(30000) !Probably rather more than is needed. CHARACTER*(*) HELLOWORLD !Believe it or not... PARAMETER (HELLOWORLD = "++++++++[>++++[>++>+++>+++>+<<<<-]" 1 //" >+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------" 2 //".--------.>>+.>++.") KBD = 5 !Standard input. MSG = 6 !Standard output. STORE = CHAR(0) !Scrub.
CALL RUN(HELLOWORLD,STORE) !Have a go.
END !Enough.</lang>
Output:
Hello World!
Compiler
Well, really a translator, as it translates the Brain*uck code into Fortran statements. This is relatively straightforward because the source code does not change and a simple translation scheme is possible. The standard problem with compilation is provided by forward references, specifically that the destination of a forwards jump is at an address that cannot be known until the code up to it has been produced. This can be handled in many ways, for instance with two passes where the first locates all the destinations so that the second can refer to them when generating code. Another method involves a "fixup table", whereby a record is kept of the locations of all leaps to as-yet unknown destinations, and when later those destinations are determined, the compiler goes back and fixes the destination fields. This all requires additional storage, in unknown amounts depending on the source being compiled.
The problem can be dodged with systems that generate say assembler source (or in this case, Fortran source) by developing some scheme for generating and using labels, merely placing them at the appropriate locations. The subsequent assembly (or Fortran compilation) will deal with these forwards references in its own way. The plan here is to recognise that a [...] sequence generates two labels, one at the location of the [ and the other at the ]. That's two labels per pair, so, count the labels and use an odd number for the [ LABEL = 2*NLABEL - 1
and the corresponding even number for the ], then keep in mind which is used at which end. Because a [...] sequence can contain nested [...] sequences, a stack is needed to keep track, and so, why not indent the source accordingly? On the other hand, there is no attempt at checking that the [...] bracketing is correct, and run-time checking that the data pointer remains within bounds is left to the Fortran compiler.
Since the increment and decrement instructions are often repeated, it is simple enough to scan ahead and count up the repetitions via a function (that also manipulates its environment), and convert a sequence of operations into a single operation. Thus, this is an optimising Brain*uck compiler!
The source involves adding a subroutine to the module and an extended main line for testing: <lang Fortran> SUBROUTINE BRAINFORT(PROG,N,INF,OUF,F) !Stand strong! Converts the Brain*uck in PROG into the equivalent furrytran source...
CHARACTER*(*) PROG !The Brain*uck source. INTEGER N !A size for the STORE. INTEGER INF,OUF,F !I/O unit numbers. INTEGER L !A stepper. INTEGER LABEL,NLABEL,INDEEP,STACK(66) !Labels cause difficulty. CHARACTER*1 C !The operation of the moment. CHARACTER*36 SOURCE !A scratchpad. WRITE (F,1) PROG,N !The programme heading. 1 FORMAT (6X,"PROGRAM BRAINFORT",/, !Name it. 1 "Code: ",A,/ !Show the provenance. 2 6X,"CHARACTER*1 STORE(",I0,")",/ !Declare the working memory. 3 6X,"INTEGER D",/ !The finger to the cell of the moment. 4 6X,"STORE = CHAR(0)",/ !Clear to nulls, not spaces. 5 6X,"D = 1",/) !Start the data finger at the first cell. NLABEL = 0 !No labels seen. INDEEP = 0 !So, the stack is empty. LABEL = 0 !And the current label is absent. L = 1 !Start at the start.
Chug through the PROG.
DO WHILE(L.LE.LEN(PROG)) !And step through to the end. C = PROG(L:L) !The code of the moment. SELECT CASE(C) !What to do? CASE(">") !Move the data finger forwards one. WRITE (SOURCE,2) "D = D + ",RATTLE(">") !But, catch multiple steps. CASE("<") !Move the data finger back one. WRITE (SOURCE,2) "D = D - ",RATTLE("<") !Rather than a sequence of one steps. CASE("+") !Increment the fingered datum by one. WRITE (SOURCE,2) "STORE(D) = CHAR(ICHAR(STORE(D)) + ", !Catching multiple increments. 1 RATTLE("+"),")" !And being careful over the placement of brackets. CASE("-") !Decrement the fingered datum by one. WRITE (SOURCE,2) "STORE(D) = CHAR(ICHAR(STORE(D)) - ", !Catching multiple decrements. 1 RATTLE("-"),")" !And closing brackets. CASE(".") !Write a character. WRITE (SOURCE,2) "WRITE (",OUF,",'(A1,$)') STORE(D)" !Using the given output unit. CASE(",") !Read a charactger. WRITE (SOURCE,2) "READ (",INF,",'(A1)') STORE(D)" !And the input unit. CASE("[") !A label! NLABEL = NLABEL + 1 !Labels come in pairs due to [...] LABEL = 2*NLABEL - 1 !So this belongs to the [. INDEEP = INDEEP + 1 !I need to remember when later the ] is encountered. STACK(INDEEP) = LABEL + 1 !This will be the other label. WRITE (SOURCE,2) "IF (ICHAR(STORE(D)).EQ.0) GO TO ", !So, go thee, therefore. 1 STACK(INDEEP) !Its placement will come, all going well. CASE("]") !The end of a [...] pair. LABEL = STACK(INDEEP) !This was the value of the label to be, now to be placed. WRITE (SOURCE,2) "IF (ICHAR(STORE(D)).NE.0) GO TO ", !The conditional part 1 LABEL - 1 !The branch back destination is known by construction. INDEEP = INDEEP - 1 !And we're out of the [...] sequence's consequences. CASE DEFAULT !All others are ignored. SOURCE = "CONTINUE" !So, just carry on. END SELECT !Enough of all that. 2 FORMAT (A,I0,A) !Text, an integer, text.
Cast forth the statement.
IF (LABEL.LE.0) THEN !Is a label waiting? WRITE (F,3) SOURCE !No. Just roll the source. 3 FORMAT (<6 + 2*MIN(12,INDEEP)>X,A)!With indentation. ELSE !But if there is a label, WRITE (F,4) LABEL,SOURCE !Slightly more complicated. 4 FORMAT (I5,<1 + 2*MIN(12,INDEEP)>X,A) !I align my labels rightwards... LABEL = 0 !It is used. END IF !So much for that statement. L = L + 1 !Advance to the next command. END DO !And perhaps we're finished.
Closedown.
WRITE (F,100) !No more source. 100 FORMAT (6X,"END") !So, this is the end. CONTAINS !A function with odd effects. INTEGER FUNCTION RATTLE(C) !Advances thrugh multiple C, counting them. CHARACTER*1 C !The symbol. RATTLE = 1 !We have one to start with. 1 IF (L.LT.LEN(PROG)) THEN !Further text to look at? IF (PROG(L + 1:L + 1).EQ.C) THEN !Yes. The same again? L = L + 1 !Yes. Advance the finger to it. RATTLE = RATTLE + 1 !Count another. GO TO 1 !And try again. END IF !Rather than just one at a time. END IF !Curse the double evaluation of WHILE(L < LEN(PROG) & ...) END FUNCTION RATTLE !Computers excel at counting. END SUBROUTINE BRAINFORT!Their only need be direction as to what to count... END MODULE BRAIN !Simple in itself.
PROGRAM POKE !A tester. USE BRAIN !In a rather bad way. CHARACTER*1 STORE(30000) !Probably rather more than is needed. CHARACTER*(*) HELLOWORLD !Believe it or not... PARAMETER (HELLOWORLD = "++++++++[>++++[>++>+++>+++>+<<<<-]" 1 //" >+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------" 2 //".--------.>>+.>++.") INTEGER F KBD = 5 !Standard input. MSG = 6 !Standard output. F = 10
STORE = CHAR(0) !Scrub.
c CALL RUN(HELLOWORLD,STORE) !Have a go.
OPEN (F,FILE="BrainFort.for",STATUS="REPLACE",ACTION="WRITE") CALL BRAINFORT(HELLOWORLD,30000,KBD,MSG,F) END !Enough.</lang>
And the output is...<lang Fortran> PROGRAM BRAINFORT Code: ++++++++[>++++[>++>+++>+++>+<<<<-] >+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.
CHARACTER*1 STORE(30000) INTEGER D STORE = CHAR(0) D = 1
STORE(D) = CHAR(ICHAR(STORE(D)) + 8) 1 IF (ICHAR(STORE(D)).EQ.0) GO TO 2 D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) + 4) 3 IF (ICHAR(STORE(D)).EQ.0) GO TO 4 D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) + 2) D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) + 3) D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) + 3) D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) + 1) D = D - 4 STORE(D) = CHAR(ICHAR(STORE(D)) - 1) 4 IF (ICHAR(STORE(D)).NE.0) GO TO 3 CONTINUE D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) + 1) D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) + 1) D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) - 1) D = D + 2 STORE(D) = CHAR(ICHAR(STORE(D)) + 1) 5 IF (ICHAR(STORE(D)).EQ.0) GO TO 6 D = D - 1 6 IF (ICHAR(STORE(D)).NE.0) GO TO 5 D = D - 1 STORE(D) = CHAR(ICHAR(STORE(D)) - 1) 2 IF (ICHAR(STORE(D)).NE.0) GO TO 1 D = D + 2 WRITE (6,'(A1,$)') STORE(D) D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) - 3) WRITE (6,'(A1,$)') STORE(D) STORE(D) = CHAR(ICHAR(STORE(D)) + 7) WRITE (6,'(A1,$)') STORE(D) WRITE (6,'(A1,$)') STORE(D) STORE(D) = CHAR(ICHAR(STORE(D)) + 3) WRITE (6,'(A1,$)') STORE(D) D = D + 2 WRITE (6,'(A1,$)') STORE(D) D = D - 1 STORE(D) = CHAR(ICHAR(STORE(D)) - 1) WRITE (6,'(A1,$)') STORE(D) D = D - 1 WRITE (6,'(A1,$)') STORE(D) STORE(D) = CHAR(ICHAR(STORE(D)) + 3) WRITE (6,'(A1,$)') STORE(D) STORE(D) = CHAR(ICHAR(STORE(D)) - 6) WRITE (6,'(A1,$)') STORE(D) STORE(D) = CHAR(ICHAR(STORE(D)) - 8) WRITE (6,'(A1,$)') STORE(D) D = D + 2 STORE(D) = CHAR(ICHAR(STORE(D)) + 1) WRITE (6,'(A1,$)') STORE(D) D = D + 1 STORE(D) = CHAR(ICHAR(STORE(D)) + 2) WRITE (6,'(A1,$)') STORE(D) END</lang>
Which, when compiled and run, produces...
Hello World!
In a transcription error, I included a space in the Brain*uck code, which was of course ignored by the interpreter. The compiler initially spat out<lang Fortran> 4 IF (ICHAR(STORE(D)).NE.0) GO TO 3
IF (ICHAR(STORE(D)).NE.0) GO TO 3</lang> because the CASE statement was followed by writing SOURCE out and the no-op had not changed it; the Fortran compiler made no complaint about the obviously pointless replication. So much for its analysis. For such "no-op" codes, fortran's CONTINUE statement is an obvious "no action" match.
FreeBASIC
<lang freebasic> ' Intérprete de brainfuck ' FB 1.05.0 Win64 '
Const BF_error_memoria_saturada As Integer = 2 Const BF_error_memoria_insuficiente As Integer = 4 Const BF_error_codigo_saturado As Integer = 8 Const BF_error_desbordamiento_codigo As Integer = 16
Dim BFcodigo As String = ">++++++++++[>+++>+++++++>++++++++++>+++++++++++>++++++++++++>++++++++++++++++[<]>-]>>>>>>+.<<<<++.>>+.---.<---.<<++.>>>+.>---.<+.<+++.>+.<<<+." Dim codigo_error As Integer
Function EjecutarBF (BFcodigo As String, tammem As Uinteger) As Integer
Dim As String memoria = String(tammem, 0) Dim As Uinteger puntero_instrucciones, puntero_datos Dim As Integer nivel_de_alcance For puntero_instrucciones = 0 To Len(BFcodigo) Select Case Chr(BFcodigo[puntero_instrucciones]) Case ">" puntero_datos += 1 If (puntero_datos > tammem - 1) Then Return BF_error_memoria_saturada Case "<" puntero_datos -= 1 If (puntero_datos > tammem - 1) Then Return BF_error_memoria_insuficiente Case "+" memoria[puntero_datos] += 1 Case "-" memoria[puntero_datos] -= 1 Case "." Print Chr(memoria[puntero_datos]); Case "," memoria[puntero_datos] = Asc(Input(1)) Case "[" If (memoria[puntero_datos] = 0) Then Dim nivel_antiguo As Uinteger = nivel_de_alcance nivel_de_alcance += 1 Do Until (nivel_de_alcance = nivel_antiguo) puntero_instrucciones += 1 If (puntero_instrucciones > Len(BFcodigo) - 1) Then Return BF_error_codigo_saturado Select Case Chr(BFcodigo[puntero_instrucciones]) Case "[" nivel_de_alcance += 1 Case "]" nivel_de_alcance -= 1 End Select Loop Else nivel_de_alcance += 1 End If Continue For Case "]" If (memoria[puntero_datos] = 0) Then nivel_de_alcance -= 1 Continue For Else Dim nivel_antiguo As Integer = nivel_de_alcance nivel_de_alcance -= 1 Do Until (nivel_de_alcance = nivel_antiguo) puntero_instrucciones -= 1 If (puntero_instrucciones > Len(BFcodigo) - 1) Then Return BF_error_desbordamiento_codigo Select Case Chr(BFcodigo[puntero_instrucciones]) Case "[" nivel_de_alcance += 1 Case "]" nivel_de_alcance -= 1 End Select Loop End If Continue For Case Else Continue For End Select Next puntero_instrucciones Return -1
End Function
Cls
codigo_error = EjecutarBF(BFcodigo, 1024)
If codigo_error Then
Sleep
Else
Print "codigo de error: " & codigo_error
End If End </lang>
- Output:
íHola mundo!
Furor
<lang Furor> argc 3 < { ."Usage: furor brainfuck.upu brainfuckpgmfile\n" }{ 2 argv getfile // dup #s print free sto bfpgm 100000 mem dup maximize sto bfmem // Memóriaallokáció a brainfuck memóriaterület számára tick sto startingtick sbr §brainfuck NL tick @startingtick #g - ."Time = " print ." tick\n" @bfmem free // A lefoglalt munkamemória felszabadítása } end // =================================================== brainfuck:
- g @bfpgm~ !{ rts } // Ha nulla a brainfuck progi hossza, semmit se kell csinálni.
zero p zero m // Indexregiszterek lenullázása (inicializálás) ((( @p @bfpgm~ < ) §jumpingtable "+-<>[].," @[]bfpgm @p // Az épp aktuális brainfuck utasítás kódja switch // Ugrás a megfelelő brainfuck funkció rutinjára ____: inc p (<) // default action _3c_: @m !{ rts } dec m goto §____ // < _3e_: @m @bfmem~ >= { rts } inc m goto §____ // > _2b_: #c @[++]bfmem @m #g goto §____ // + _2d_: #c @[--]bfmem @m #g goto §____ // - _2c_: @bfmem @m getchar [^] goto §____ _2e_: @[]bfmem @m printchar goto §____ _5b_: @[]bfmem @m then §____
zero d @p ++ @bfpgm~ {|| {} []@bfpgm '[ == { inc d {<} } {} []@bfpgm '] == { @d !{ {+} sto p {>} } dec d }
|} (<) _5d_: zero d 1 @p {|| {-} []@bfpgm '] == { inc d {<} }
{-} []@bfpgm '[ == { @d !{ {} !sum p {>} } dec d }
|} (<) )) rts // =================================================== { „startingtick” } { „bfpgm” } { „bfmem” } { „p” /* index az épp végrehajtandó brainfuck mnemonikra */ } { „m” /* index a brainfuck memóriaterületre */ } { „d” /* munkaváltozó */ } // ======================================== jumpingtable: // + - < > [ ] . , §_2b_ §_2d_ §_3c_ §_3e_ §_5b_ §_5d_ §_2e_ §_2c_ </lang>
Yet another solution:
<lang Furor>
- sysinclude stringextra.uh
argc 3 < { ."Usage: furor brainfuck.upu brainfuckpgmfile\n" }{ 2 argv getfile sto bfpgm bfpgm '< >><< bfpgm '> >><< 100000 mem dup maximize sto bfmem // Memóriaallokáció a brainfuck memóriaterület számára tick sto startingtick sbr §brainfuck NL tick @startingtick #g - ."Time = " print ." tick\n" @bfmem free // A lefoglalt munkamemória felszabadítása } end // =================================================== brainfuck:
- g @bfpgm~ !{ rts } // Ha nulla a brainfuck progi hossza, semmit se kell csinálni.
zero p zero m // Indexregiszterek lenullázása (inicializálás) ((( @p @bfpgm~ < ) @p *2 [#n]@bfpgm // Az épp aktuális brainfuck utasítás kódja §jumpingtable[] [goto] // Ugrás a megfelelő brainfuck funkció rutinjára
____: inc p (<)
_3c_: @m !{ rts } @[]bfpgm @p 32 >> !sum m goto §____ // < _3e_: @m @bfmem~ >= { rts } @[]bfpgm @p 32 >> sum m goto §____ // >
_2b_: #c @[++]bfmem @m #g goto §____ // + _2d_: #c @[--]bfmem @m #g goto §____ // - _2c_: @bfmem @m getchar [^] goto §____ _2e_: @[]bfmem @m printchar goto §____ _5b_: @[]bfmem @m then §____
zero d @p ++ @bfpgm {~| @@ '[ == { inc d {<} } @@ '] == { @d !{ {+} sto p {>} } dec d }
|} (<)
_5d_: zero d 1 @p {|| {-} []@bfpgm '] == { inc d {<} }
{-} []@bfpgm '[ == { @d !{ {} !sum p {>} } dec d }
|} (<) )) rts // =================================================== { „startingtick” } { „bfpgm” } { „bfmem” } { „p” /* index az épp végrehajtandó brainfuck mnemonikra */ } { „m” /* index a brainfuck memóriaterületre */ } { „d” /* munkaváltozó */ } // ======================================== jumpingtable: // 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f /* 00 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 01 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 02 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §_2b_ §_2c_ §_2d_ §_2e_ §____ /* 03 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §_3c_ §____ §_3e_ §____ /* 04 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 05 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §_5b_ §____ §_5d_ §____ §____ /* 06 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 07 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 08 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 09 */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 0a */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 0b */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 0c */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 0d */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 0e */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ /* 0f */ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____ §____
</lang>
GAP
<lang gap># Here . and , print and read an integer, not a character Brainfuck := function(prog)
local pointer, stack, leftcells, rightcells, instr, stackptr, len, output, input, jump, i, j, set, get; input := InputTextUser(); output := OutputTextUser(); instr := 1; pointer := 0; leftcells := [ ]; rightcells := [ ]; stack := [ ]; stackptr := 0; len := Length(prog); jump := [ ];
get := function() local p; if pointer >= 0 then p := pointer + 1; if IsBound(rightcells[p]) then return rightcells[p]; else return 0; fi; else p := -pointer; if IsBound(leftcells[p]) then return leftcells[p]; else return 0; fi; fi; end; set := function(value) local p; if pointer >= 0 then p := pointer + 1; if value = 0 then Unbind(rightcells[p]); else rightcells[p] := value; fi; else p := -pointer; if value = 0 then Unbind(leftcells[p]); else leftcells[p] := value; fi; fi; end; # find jumps for faster execution for i in [1 .. len] do if prog[i] = '[' then stackptr := stackptr + 1; stack[stackptr] := i; elif prog[i] = ']' then j := stack[stackptr]; stackptr := stackptr - 1; jump[i] := j; jump[j] := i; fi; od;
while instr <= len do c := prog[instr]; if c = '<' then pointer := pointer - 1; elif c = '>' then pointer := pointer + 1; elif c = '+' then set(get() + 1); elif c = '-' then set(get() - 1); elif c = '.' then WriteLine(output, String(get())); elif c = ',' then set(Int(Chomp(ReadLine(input)))); elif c = '[' then if get() = 0 then instr := jump[instr]; fi; elif c = ']' then if get() <> 0 then instr := jump[instr]; fi; fi; instr := instr + 1; od; CloseStream(input); CloseStream(output); # for debugging purposes, return last state return [leftcells, rightcells, pointer];
end;
- An addition
Brainfuck("+++.<+++++.[->+<]>.");
- 3
- 5
- 8</lang>
Go
Fixed size data store, no bounds checking. <lang go>package main
import "fmt"
func main() {
// example program is current Brain**** solution to // Hello world/Text task. only requires 10 bytes of data store! bf(10, `++++++++++[>+>+++>++++>+++++++>++++++++>+++++++++>++
++++++++>+++++++++++>++++++++++++<<<<<<<<<-]>>>>+.>>> >+..<.<++++++++.>>>+.<<+.<<<<++++.<++.>>>+++++++.>>>.+++. <+++++++.--------.<<<<<+.<+++.---.`) }
func bf(dLen int, is string) {
ds := make([]byte, dLen) // data store var dp int // data pointer for ip := 0; ip < len(is); ip++ { switch is[ip] { case '>': dp++ case '<': dp-- case '+': ds[dp]++ case '-': ds[dp]-- case '.': fmt.Printf("%c", ds[dp]) case ',': fmt.Scanf("%c", &ds[dp]) case '[': if ds[dp] == 0 { for nc := 1; nc > 0; { ip++ if is[ip] == '[' { nc++ } else if is[ip] == ']' { nc-- } } } case ']': if ds[dp] != 0 { for nc := 1; nc > 0; { ip-- if is[ip] == ']' { nc++ } else if is[ip] == '[' { nc-- } } } } }
}</lang>
- Output:
Goodbye, World!
Groovy
<lang groovy>class BrainfuckProgram {
def program = , memory = [:] def instructionPointer = 0, dataPointer = 0
def execute() { while (instructionPointer < program.size()) switch(program[instructionPointer++]) { case '>': dataPointer++; break; case '<': dataPointer--; break; case '+': memory[dataPointer] = memoryValue + 1; break case '-': memory[dataPointer] = memoryValue - 1; break case ',': memory[dataPointer] = System.in.read(); break case '.': print String.valueOf(Character.toChars(memoryValue)); break case '[': handleLoopStart(); break case ']': handleLoopEnd(); break } }
private getMemoryValue() { memory[dataPointer] ?: 0 }
private handleLoopStart() { if (memoryValue) return
int depth = 1 while (instructionPointer < program.size()) switch(program[instructionPointer++]) { case '[': depth++; break case ']': if (!(--depth)) return } throw new IllegalStateException('Could not find matching end bracket') }
private handleLoopEnd() { int depth = 0 while (instructionPointer >= 0) { switch(program[--instructionPointer]) { case ']': depth++; break case '[': if (!(--depth)) return; break } } throw new IllegalStateException('Could not find matching start bracket') }
}</lang> Testing: <lang groovy>new BrainfuckProgram(program: '++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.').execute()</lang>
- Output:
Hello World!
Haskell
Icon and Unicon
Implementation in Icon/Unicon.
J
Janet
Java
import java.io.IOException; public class Interpreter { public final static int MEMORY_SIZE = 65536; private final char[] memory = new char[MEMORY_SIZE]; private int dp; private int ip; private int border; private void reset() { for (int i = 0; i < MEMORY_SIZE; i++) { memory[i] = 0; } ip = 0; dp = 0; } private void load(String program) { if (program.length() > MEMORY_SIZE - 2) { throw new RuntimeException("Not enough memory."); } reset(); for (; dp < program.length(); dp++) { memory[dp] = program.charAt(dp); } // memory[border] = 0 marks the end of instructions. dp (data pointer) cannot move lower than the // border into the program area. border = dp; dp += 1; } public void execute(String program) { load(program); char instruction = memory[ip]; while (instruction != 0) { switch (instruction) { case '>': dp++; if (dp == MEMORY_SIZE) { throw new RuntimeException("Out of memory."); } break; case '<': dp--; if (dp == border) { throw new RuntimeException("Invalid data pointer."); } break; case '+': memory[dp]++; break; case '-': memory[dp]--; break; case '.': System.out.print(memory[dp]); break; case ',': try { // Only works for one byte characters. memory[dp] = (char) System.in.read(); } catch (IOException e) { throw new RuntimeException(e); } break; case '[': if (memory[dp] == 0) { skipLoop(); } break; case ']': if (memory[dp] != 0) { loop(); } break; default: throw new RuntimeException("Unknown instruction."); } instruction = memory[++ip]; } } private void skipLoop() { int loopCount = 0; while (memory[ip] != 0) { if (memory[ip] == '[') { loopCount++; } else if (memory[ip] == ']') { loopCount--; if (loopCount == 0) { return; } } ip++; } if (memory[ip] == 0) { throw new RuntimeException("Unable to find a matching ']'."); } } private void loop() { int loopCount = 0; while (ip >= 0) { if (memory[ip] == ']') { loopCount++; } else if (memory[ip] == '[') { loopCount--; if (loopCount == 0) { return; } } ip--; } if (ip == -1) { throw new RuntimeException("Unable to find a matching '['."); } } public static void main(String[] args) { Interpreter interpreter = new Interpreter(); interpreter.execute(">++++++++[-<+++++++++>]<.>>+>-[+]++>++>+++[>[->+++<<+++>]<<]>-----.>->+++..+++.>-.<<+[>[+>+]>>]<--------------.>>.+++.------.--------.>+.>+."); } }
JavaScript
Jsish
Part of the Jsi source kit unit tests. bf code from Hello World/text task entry.
<lang javascript>/*
* javascript bf interpreter * by wenxichang@163.com */
function execute(code) {
var mem = new Array(30000); var sp = 10000; var opcode = new String(code); var oplen = opcode.length; var ip = 0; var loopstack = new Array(); var output = ""; for (var i = 0; i < 30000; ++i) mem[i] = 0; while (ip < oplen) { switch(opcode[ip]) { case '+': mem[sp]++; break; case '-': mem[sp]--; break; case '>': sp++; break; case '<': sp--; break; case '.': if (mem[sp] != 10 && mem[sp] != 13) { output = output + Util.fromCharCode(mem[sp]); } else { puts(output); output = ""; } break; case ',': var s = console.input(); if (!s) exit(0); mem[sp] = s.charCodeAt(0); break; case '[': if (mem[sp]) { loopstack.push(ip); } else { for (var k = ip, j = 0; k < oplen; k++) { opcode[k] == '[' && j++; opcode[k] == ']' && j--; if (j == 0) break; } if (j == 0) ip = k; else { puts("Unmatched loop"); return false; } } break; case ']': ip = loopstack.pop() - 1; break; default: break; } ip++; } return true;
};
if (Interp.conf('unitTest') > 0) execute('
++++++++++[>+>+++>++++>+++++++ >++++++++>+++++++++>++++++++++>+++++++++ ++>++++++++++++<<<<<<<<<-]>>>>+.>>>>+..<.<++++++++.>>>+.<<+.<<<<++++.<+ +.>>>+++++++.>>>.+++.<+++++++.--------.<<<<<+.<+++.---.
');</lang>
- Output:
prompt$ jsish --U bf.jsi Goodbye, World!
Julia
<lang julia>using DataStructures
function execute(src)
pointers = Dict{Int,Int}() stack = Int[] for (ptr, opcode) in enumerate(src) if opcode == '[' push!(stack, ptr) end if opcode == ']' if isempty(stack) src = src[1:ptr] break end sptr = pop!(stack) pointers[ptr], pointers[sptr] = sptr, ptr end end if ! isempty(stack) error("unclosed loops at $stack") end tape = DefaultDict{Int,Int}(0) cell, ptr = 0, 1 while ptr ≤ length(src) opcode = src[ptr] if opcode == '>' cell += 1 elseif opcode == '<' cell -= 1 elseif opcode == '+' tape[cell] += 1 elseif opcode == '-' tape[cell] -= 1 elseif opcode == ',' tape[cell] = Int(read(STDIN, 1)) elseif opcode == '.' print(STDOUT, Char(tape[cell])) elseif (opcode == '[' && tape[cell] == 0) || (opcode == ']' && tape[cell] != 0) ptr = pointers[ptr] end ptr += 1 end
end
const src = """\
>++++++++[<+++++++++>-]<.>>+>+>++>[-]+<[>[->+<<++++>]<<]>.+++++++..+++.> >+++++++.<<<[[-]<[-]>]<+++++++++++++++.>>.+++.------.--------.>>+.>++++."""
execute(src)</lang>
- Output:
Hello World!
Kotlin
<lang scala>// version 1.1.2
class Brainf__k(val prog: String, memSize: Int) {
private val mem = IntArray(memSize) private var ip = 0 private var dp = 0 private val memVal get() = mem.getOrElse(dp) { 0 }
fun execute() { while (ip < prog.length) { when (prog[ip++]) { '>' -> dp++ '<' -> dp-- '+' -> mem[dp] = memVal + 1 '-' -> mem[dp] = memVal - 1 ',' -> mem[dp] = System.`in`.read() '.' -> print(memVal.toChar()) '[' -> handleLoopStart() ']' -> handleLoopEnd() } } }
private fun handleLoopStart() { if (memVal != 0) return var depth = 1 while (ip < prog.length) { when (prog[ip++]) { '[' -> depth++ ']' -> if (--depth == 0) return } } throw IllegalStateException("Could not find matching end bracket") }
private fun handleLoopEnd() { var depth = 0 while (ip >= 0) { when (prog[--ip]) { ']' -> depth++ '[' -> if (--depth == 0) return } } throw IllegalStateException("Could not find matching start bracket") }
}
fun main(args: Array<String>) {
val prog = "++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>." Brainf__k(prog, 10).execute()
}</lang>
- Output:
Hello World!
Limbo
Expects the program to be the first argument, compiles to bytecode (without optimization), uses a 1MB array of cells (and wraps), includes some rudimentary compiler diagnostics.
<lang Limbo>implement Bf;
include "sys.m"; sys: Sys; include "draw.m";
Bf: module { init: fn(nil: ref Draw->Context, args: list of string); ARENASZ: con 1024 * 1024; EXIT, INC, DEC, JZ, JNZ, INCP, DECP, READ, WRITE: con iota; };
init(nil: ref Draw->Context, args: list of string) { sys = load Sys Sys->PATH; args = tl args; if(args == nil || len args != 1) { sys->fprint(sys->fildes(2), "usage: bf program"); raise "fail:usage"; } code := compile(hd args); execute(code, array[ARENASZ] of { * => byte 0 }); }
compile(p: string): array of int { marks: list of int = nil; code := array[len p * 2 + 1] of { * => EXIT }; pc := 0; for(i := 0; i < len p; i++) { case p[i] { '-' => code[pc++] = DEC; '+' => code[pc++] = INC; '<' => code[pc++] = DECP; '>' => code[pc++] = INCP; ',' => code[pc++] = READ; '.' => code[pc++] = WRITE; '[' => code[pc++] = JZ; marks = pc++ :: marks; ']' => if(marks == nil) { sys->fprint(sys->fildes(2), "bf: unmatched ']' at character %d.", pc); raise "fail:errors"; } c := hd marks; marks = tl marks; code[pc++] = JNZ; code[c] = pc; code[pc++] = c; } } if(marks != nil) { sys->fprint(sys->fildes(2), "bf: unmatched '['."); raise "fail:errors"; } return code; }
execute(code: array of int, arena: array of byte) { pc := 0; p := 0; buf := array[1] of byte; stopreading := 0; for(;;) { case code[pc] { DEC => arena[p]--; INC => arena[p]++; DECP => p--; if(p < 0) p = len arena - 1; INCP => p = (p + 1) % len arena; READ => if(!stopreading) { n := sys->read(sys->fildes(0), buf, 1); if(n < 1) { arena[p] = byte 0; stopreading = 1; } else { arena[p] = buf[0]; } } WRITE => buf[0] = arena[p]; sys->write(sys->fildes(1), buf, 1); JNZ => if(arena[p] != byte 0) pc = code[pc + 1]; else pc++; JZ => if(arena[p] == byte 0) pc = code[pc + 1]; else pc++; EXIT => return; } pc++; } } </lang>
- Output:
Using the example code from Hello world/Text:
% bf '++++++++++[>+>+++>++++>+++++++>++++++++>+++++++++>++ ++++++++>+++++++++++>++++++++++++<<<<<<<<<-]>>>>+.>>> >+..<.<++++++++.>>>+.<<+.<<<<++++.<++.>>>+++++++.>>>.+++. <+++++++.--------.<<<<<+.<+++.---.' Goodbye, World!
Lua
Simple meta-implementation using load
<lang Lua>local funs = { ['>'] = 'ptr = ptr + 1; ', ['<'] = 'ptr = ptr - 1; ', ['+'] = 'mem[ptr] = mem[ptr] + 1; ', ['-'] = 'mem[ptr] = mem[ptr] - 1; ', ['['] = 'while mem[ptr] ~= 0 do ', [']'] = 'end; ', ['.'] = 'io.write(string.char(mem[ptr])); ', [','] = 'mem[ptr] = (io.read(1) or "\\0"):byte(); ', }
local prog = [[
local mem = setmetatable({}, { __index = function() return 0 end}) local ptr = 1
]]
local source = io.read('*all')
for p = 1, #source do
local snippet = funs[source:sub(p,p)] if snippet then prog = prog .. snippet end
end
load(prog)()</lang>
BTW very fast, considering how simple it is.
M2000 Interpreter
<lang M2000 Interpreter> Module Checkit {
\\ Brain**** Compiler Escape Off \\ no Esc function so we can use Ctrl+Z when input characters to terminate BF \\ ctrl+c open dialog for exit - by default in console mode Const skipmonitor as boolean=true, output as boolean=True Const ob$="{",cb$="}" Gosub CallOne \\ We use a group object with events. Group WithEvents BF=BrainF() Function BF_monitor { \\ Event functions have same scope as the module where belong If skipmonitor Then exit Read New pc, mem Print pc, mem Print "Press space bar": While Key$<>" " {} } Function BF_newline { If not skipmonitor then Print "newline" : exit if output then Print } Function BF_print { Read New c$ If not skipmonitor then Print "character:";c$ : exit if output then Print c$; } Program$ = {++++++[>++++++++++++<-]>. >++++++++++[>++++++++++<-]>+. +++++++..+++.>++++[>+++++++++++<-]>. <+++[>----<-]>.<<<<<+++[>+++++<-]>. >>.+++.------.--------.>>+. } Report Program$ ExecBF(Program$) End Sub ExecBF(Code$) ClearMem() code$=filter$(code$, " "+chr$(10)+chr$(13)) code$<=replace$(".","@", code$) code$<=replace$("-","-.D()", code$) code$<=replace$("+","-.A()", code$) code$<=replace$("<","-.L()", code$) code$<=replace$(">","-.R()", code$) code$<=replace$("@","-.P()", code$) code$<=replace$("[","-.S("+ob$,code$) code$<=replace$("]",cb$+")",code$) code$<=replace$(",","-.K()", code$) Rem : Print code$ BF.Eval code$ Print End Sub Sub ClearMem() Dim cMem(1 to 30000)=0 For BF { .Pc=1 .Zero=True .Mem()=cMem() } End Sub CallOne: Class BrainF { events "monitor", "newline", "print" Dim Mem() Pc=1, Zero as Boolean=True Module UpdateZero { .Zero<=.Mem(.Pc)=0 call event "monitor", .pc, .Mem(.pc) } Function A { \\ + .Mem(.Pc)++ .UpdateZero } Function D { \\ - .Mem(.Pc)-- .UpdateZero } Function R { \\ > If .Pc=30000 Then Error "Upper Bound Error" .Pc++ .UpdateZero } Function L { \\ < If .Pc=1 Then Error "Lower Bound Error" .Pc-- .UpdateZero } Function P { \\ . Select Case .Mem(.Pc) Case >31 Call Event "print", Chr$(.Mem(.Pc)) Case 10 Call Event "newline" End Select } Function K { \\ , .Mem(.Pc)=Asc(Key$) \\ ctrl+z for exit If .Mem(.Pc)=26 Then Error "Finished" .UpdateZero } Function S { \\ [ If .Zero then =0: exit Read newEval$ Do {ret=Eval(newEval$)} until .Zero } Module Eval { ret=eval(Letter$) } } Return
} Checkit </lang>
Mathematica / Wolfram Language
<lang>bf[program_, input_] :=
Module[{p = Characters[program], pp = 0, m, mp = 0, bc = 0, instr = StringToStream[input]}, m[_] = 0; While[pp < Length@p, pp++; Switch[ppp, ">", mp++, "<", mp--, "+", m[mp]++, "-", m[mp]--, ".", BinaryWrite["stdout", m[mp]], ",", m[mp] = BinaryRead[instr], "[", If[m[mp] == 0, bc = 1; While[bc > 0, pp++; Switch[ppp, "[", bc++, "]", bc--]]], "]", If[m[mp] != 0, bc = -1; While[bc < 0, pp--; Switch[ppp, "[", bc++, "]", bc--]]]]]; Close[instr];];
bf[program_] := bf[program, ""]</lang>
Example:
<lang>bf["++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++. <<+++++++++++++++.>.+++.------.--------.>+.>."]</lang>
- Output:
Hello World!
Modula-3
Nanoquery
<lang Nanoquery>// nanoquery has no function to get just a character // so we have to implement our own def get_char()
c = "" while len(c)=0 c = input() end return c[0]
end
// a function to handle fatal errors def fatal_error(errtext)
println "%" + errtext println "usage: " + args[1] + " [filename.bf]" exit
end
// get a filename from the command line and read the file in fname = null source = null try
fname = args[2] source = new(Nanoquery.IO.File, fname).readAll()
catch
fatal_error("error while trying to read from specified file")
end
// start with one hundred cells and the pointer at 0 cells = {0} * 100 ptr = 0
// loop through the instructions loc = 0 while loc < len(source)
instr = source[loc] if instr = ">" ptr += 1 if ptr = len(cells) cells.append(0) end else if instr = "<" ptr -= 1 if ptr < 0 ptr = 0 end else if instr = "+" cells[ptr] += 1 else if instr = "-" cells[ptr] -= 1 else if instr = "." print chr(cells[ptr]) else if instr = "," cells[ptr] = ord(get_char()) else if instr = "[" if cells[ptr] = 0 while source[loc] != "]" loc += 1 end end else if instr = "]" if cells[ptr] != 0 while source[loc] != "[" loc -= 1 end end else // do nothing end
loc += 1
end</lang>
Never
<lang never> record BFI {
cmd : char; next : BFI; jmp : BFI;
}
record MEM {
val : int; next : MEM; prev : MEM;
}
func compile(prog : string) -> BFI {
var i = 0; var n = BFI; var p = BFI; var j = BFI; var pgm = BFI; for (i = 0; i < length(prog); i = i + 1) { n = BFI('0', nil, nil); if (p != nil) { p.next = n } else { pgm = n }; n.cmd = prog[i]; p = n; if (prog[i] == '[') { n.jmp = j; j = n; 0 } else if (prog[i] == ']') { n.jmp = j; j = j.jmp; n.jmp.jmp = n; 0 } else { 0 } }; pgm
}
func exec(pgm : BFI) -> int {
var m = MEM(0, nil, nil); var n = BFI;
for (n = pgm; n != nil; n = n.next) { if (n.cmd == '+') { m.val = m.val + 1 } else if (n.cmd == '-') { m.val = m.val - 1 } else if (n.cmd == '.') { printc(chr(m.val)); 0 } else if (n.cmd == ',') { m.val = read() } else if (n.cmd == '[') { if (m.val == 0) { n = n.jmp; 0 } else { 0 } } else if (n.cmd == ']') { if (m.val != 0) { n = n.jmp; 0 } else { 0 } } else if (n.cmd == '<') { m = m.prev; 0 } else if (n.cmd == '>') { if (m.next == nil) { m.next = MEM(0, nil, nil); m.next.prev = m; 0 } else { 0 };
m = m.next; 0 } else { 0 } }; 0
}
func run(prog : string) -> int {
var pgm = BFI;
pgm = compile(prog); exec(pgm); 0
}
func main() -> int {
/* Hello World! */ run("++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++."); 0
} </lang>
Nim
<lang nim>import os
var
code = if paramCount() > 0: readFile paramStr 1 else: readAll stdin tape = newSeq[char]() d = 0 i = 0
proc run(skip = false): bool =
while d >= 0 and i < code.len: if d >= tape.len: tape.add '\0'
if code[i] == '[': inc i let p = i while run(tape[d] == '\0'): i = p elif code[i] == ']': return tape[d] != '\0' elif not skip: case code[i] of '+': inc tape[d] of '-': dec tape[d] of '>': inc d of '<': dec d of '.': stdout.write tape[d] of ',': tape[d] = stdin.readChar else: discard
inc i
discard run()</lang>
- Output:
If given in input the string ++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.
, output is:
Hello World!
Objeck
<lang objeck>class Brainfu_k {
@program : String; @mem : Int[]; @ip : Int; @dp : Int; New(program : String, size : Int) { @program := program; @mem := Int → New[size]; } function : Main(args : String[]) ~ Nil { if(args → Size() = 2) { Brainfu_k → New(args[0], args[1] → ToInt()) → Execute(); }; } method : Execute() ~ Nil { while(@ip < @program → Size()) { instr := @program → Get(@ip); select(instr) { label '>': { @dp += 1; } label '<': { @dp -= 1; } label '+': { @mem[@dp] := @mem[@dp] + 1; } label '-': { @mem[@dp] := @mem[@dp] - 1; } label '.': { value := @mem[@dp] → As(Char); value → Print(); } label ',': { @mem[@dp] := Read(); } label '[': { JumpForward(); } label ']': { JumpBack(); } }; @ip += 1; }; } method : JumpForward() ~ Nil { depth := 1; if(@mem[@dp] = 0) { while(@ip < @program → Size()) { instr := @program → Get(@ip); if(instr = ']') { depth -= 1; if(depth = 0) { return; }; } else if(instr = '[') { depth += 1; }; @ip += 1; }; "*** Unbalanced jump ***" → ErrorLine(); Runtime → Exit(1); }; } method : JumpBack() ~ Nil { depth := 1; if(@mem[@dp] <> 0) { while(@ip > 0) { @ip -= 1; instr := @program → Get(@ip); if(instr = '[') { depth -= 1; if(depth = 0) { return; }; } else if(instr = ']') { depth += 1; }; }; "*** Unbalanced jump ***" → ErrorLine(); Runtime → Exit(1); }; } method : Read() ~ Int { in := IO.Console → ReadString(); if(in → Size() > 0) { return in → ToInt(); }; return 0; }
}</lang>
OCaml
Ol
(without input operator ",") <lang ol> (define (bf program stack-length)
(let ((program (string-append program "]")) (program-counter 0) (stack (make-vector stack-length 0)) (stack-pointer 0)) (letrec ((skip (lambda (PC sp) (let loop ((pc PC) (sp sp)) (let ((ch (string-ref program pc)) (pc (+ pc 1))) (case ch (#\] (list pc sp)) (#\[ (apply loop (skip pc sp))) (else (loop pc sp))))))) (step (lambda (PC SP) (let loop ((pc PC) (sp SP)) (let ((ch (string-ref program pc)) (pc (+ pc 1))) (case ch (#\] (list (- PC 1) sp)) (#\[ (if (eq? (vector-ref stack sp) 0) (apply loop (skip pc sp)) (apply loop (step pc sp)))) (#\+ (set-ref! stack sp (+ (vector-ref stack sp) 1)) (loop pc sp)) (#\- (set-ref! stack sp (- (vector-ref stack sp) 1)) (loop pc sp)) (#\> (loop pc (+ sp 1))) (#\< (loop pc (- sp 1))) (#\. (display (make-string 1 (vector-ref stack sp))) (loop pc sp)) (else (loop pc sp)))))))) (step 0 0))))
- testing
- (bf ",++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>." 30000)
- ==> Hello World!
- (bf ">>++++[<++++[<++++>-]>-]<<.[-]++++++++++." 30000)
- ==> @
</lang>
PARI/GP
A case statement would have been really useful here... <lang parigp>BF(prog)={ prog=Vec(Str(prog)); my(codeptr,ptr=1,v=vector(1000),t); while(codeptr++ <= #prog, t=prog[codeptr]; if(t=="+", v[ptr]++ , if(t=="-", v[ptr]-- , if(t==">", ptr++ , if(t=="<", ptr-- , if(t=="[" && !v[ptr], t=1; while(t, if(prog[codeptr++]=="[",t++); if(prog[codeptr]=="]",t--) ); ); if(t=="]"&&v[ptr], t=1; while(t, if(prog[codeptr--]=="[",t--); if(prog[codeptr]=="]",t++) ) ); if(t==".", print1(Strchr(v[ptr])) ); if(t==",", v[ptr]=Vecsmall(input)[1] ) ) ) ) ) ) };</lang>
Pascal
<lang Pascal> program rcExceuteBrainF;
uses
Crt;
Const
DataSize= 1024; // Size of Data segment MaxNest= 1000; // Maximum nesting depth of []
procedure ExecuteBF(Source: string); var
Dp: pByte; // Used as the Data Pointer DataSeg: Pointer; // Start of the DataSegment (Cell 0) Ip: pChar; // Used as instruction Pointer LastIp: Pointer; // Last adr of code. JmpStack: array[0..MaxNest-1] of pChar; // Stack to Keep track of active "[" locations JmpPnt: Integer; // Stack pointer ^^ JmpCnt: Word; // Used to count brackets when skipping forward.
begin
// Set up then data segment getmem(DataSeg,dataSize); dp:=DataSeg; fillbyte(dp^,dataSize,0);
// Set up the JmpStack JmpPnt:=-1;
// Set up Instruction Pointer Ip:=@Source[1]; LastIp:=@Source[length(source)]; if Ip=nil then exit;
// Main Execution loop repeat { until Ip > LastIp } Case Ip^ of '<': dec(dp); '>': inc(dp); '+': inc(dp^); '-': dec(dp^); '.': write(stdout,chr(dp^)); ',': dp^:=ord(readkey); '[': if dp^=0 then begin // skip forward until matching bracket; JmpCnt:=1; while (JmpCnt>0) and (ip<=lastip) do begin inc(ip); Case ip^ of '[': inc(JmpCnt); ']': dec(JmpCnt); #0: begin Writeln(StdErr,'Error brackets dont match'); halt; end; end; end; end else begin // Add location to Jump stack inc(JmpPnt); JmpStack[jmpPnt]:=ip; end; ']': if dp^>0 then // Jump Back to matching [ ip:=JmpStack[jmpPnt] else // Remove Jump from stack dec(jmpPnt); end; inc(ip); until Ip>lastIp; freemem(DataSeg,dataSize);
end;
Const
HelloWorldWiki = '++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>'+ '---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.';
pressESCtoCont = '>[-]+++++++[<++++++++++>-]<->>[-]+++++++[<+++++++++++'+ '+>-]<->>[-]++++[<++++++++>-]+>[-]++++++++++[<++++++++'+ '++>-]>[-]++++++++[<++++++++++++++>-]<.++.+<.>..<<.<<.'+ '-->.<.>>.>>+.-----.<<.[<<+>>-]<<.>>>>.-.++++++.<++++.'+ '+++++.>+.<<<<++.>+[>+<--]>++++...'; waitForEsc = '[-]>[-]++++[<+++++++>-]<->[-]>+[[-]<<[>+>+<<-]'+'>>[<'+ '<+>>-],<[->-<]>]';
begin
// Execute "Hello World" example from Wikipedia ExecuteBF(HelloWorldWiki);
// Print text "press ESC to continue....." and wait for ESC to be pressed ExecuteBF(pressESCtoCont+waitForEsc);
end.
</lang>
Perl
Phix
<lang Phix>procedure bfi(string pgm) sequence jumptable = repeat(0,length(pgm)),
loopstack = {}, data = repeat(0,10) -- size??
integer skip = 0, ch, loopstart, pc, dp
-- -- compile (pack/strip comments and link jumps) -- for i=1 to length(pgm) do ch = pgm[i] switch ch do case '[': loopstack = append(loopstack,i-skip); pgm[i-skip] = ch; case ']': loopstart = loopstack[$]; loopstack = loopstack[1..-2]; jumptable[i-skip] = loopstart; jumptable[loopstart] = i-skip; fallthrough case '+','-','<','>',',','.': pgm[i-skip] = ch; default: skip += 1 end switch end for if length(loopstack) then ?9/0 end if pgm = pgm[1..-1-skip]
-- -- main execution loop -- pc = 1 dp = 1 while pc<=length(pgm) do ch = pgm[pc] switch ch do case '>': dp += 1 if dp>length(data) then dp = 1 end if case '<': dp -= 1 if dp<1 then dp = length(data) end if case '+': data[dp] += 1 case '-': data[dp] -= 1 case ',': data[dp] = getc(0) case '.': puts(1,data[dp]) case '[': if data[dp]=0 then pc = jumptable[pc] end if case ']': if data[dp]!=0 then pc = jumptable[pc] end if default: ?9/0 end switch pc += 1 end while
end procedure
constant bf="++++++++[>++++[>++>++++>+++>+<<<<-]>++>->+>>+[<]<-]>>.>>.+.<.>>.<<<++.>---------.>------.<----.++++++++.>>+.>++.+++." constant fb="++++++++[>++++[>++>++++>+++>+<<<<-]>++>->+>>+[<]<-]>>.>>.+.<.>>.<<<+++.>---.>------.++++++++.<--.>>+.>++.+++.,"
bfi(bf) bfi(fb)</lang>
- Output:
Phix Rocks! Phix Sucks!
PHP
<lang php><?php function brainfuck_interpret(&$s, &$_s, &$d, &$_d, &$i, &$_i, &$o) {
do { switch($s[$_s]) { case '+': $d[$_d] = chr(ord($d[$_d]) + 1); break; case '-': $d[$_d] = chr(ord($d[$_d]) - 1); break; case '>': $_d++; if(!isset($d[$_d])) $d[$_d] = chr(0); break; case '<': $_d--; break; case '.': $o .= $d[$_d]; break; case ',': $d[$_d] = $_i==strlen($i) ? chr(0) : $i[$_i++]; break; case '[': if((int)ord($d[$_d]) == 0) { $brackets = 1; while($brackets && $_s++ < strlen($s)) { if($s[$_s] == '[') $brackets++; else if($s[$_s] == ']') $brackets--; } } else { $pos = $_s++-1; if(brainfuck_interpret($s, $_s, $d, $_d, $i, $_i, $o)) $_s = $pos; } break; case ']': return ((int)ord($d[$_d]) != 0); } } while(++$_s < strlen($s));
}
function brainfuck($source, $input=) {
$data = array(); $data[0] = chr(0); $data_index = 0; $source_index = 0; $input_index = 0; $output = ; brainfuck_interpret($source, $source_index, $data, $data_index, $input, $input_index, $output); return $output;
}
$code = "
>++++++++[<+++++++++>-]<.>>+>+>++>[-]+<[>[->+<<++++>]<<]>.+++++++..+++.> >+++++++.<<<[[-]<[-]>]<+++++++++++++++.>>.+++.------.--------.>>+.>++++.
"; $inp = '123'; print brainfuck( $code, $inp ); </lang>
PicoLisp
This solution uses a doubly-linked list for the cell space. That list consists of a single cell initially, and grows automatically in both directions. The value in each cell is unlimited. <lang PicoLisp>(off "Program")
(de compile (File)
(let Stack NIL (setq "Program" (make (in File (while (char) (case @ (">" (link '(setq Data (or (cddr Data) (con (cdr Data) (cons 0 (cons Data))) ) ) ) ) ("<" (link '(setq Data (or (cadr Data) (set (cdr Data) (cons 0 (cons NIL Data))) ) ) ) ) ("+" (link '(inc Data))) ("-" (link '(dec Data))) ("." (link '(prin (char (car Data))))) ("," (link '(set Data (char (read))))) ("[" (link '(setq Code ((if (=0 (car Data)) cdar cdr) Code) ) ) (push 'Stack (chain (cons))) ) ("]" (unless Stack (quit "Unbalanced ']'") ) (link '(setq Code ((if (n0 (car Data)) cdar cdr) Code) ) ) (let (There (pop 'Stack) Here (cons There)) (chain (set There Here)) ) ) ) ) ) ) ) (when Stack (quit "Unbalanced '['") ) ) )
(de execute ()
(let Data (cons 0 (cons)) # Create initial cell (for (Code "Program" Code) # Run program (eval (pop 'Code)) ) (while (cadr Data) # Find beginning of data (setq Data @) ) (filter prog Data '(T NIL .)) ) ) # Return data space</lang>
- Output:
: (compile "hello.bf") -> NIL : (execute) Goodbye, World! -> (0 10 33 44 71 87 98 100 114 121)
Alternative solution
# This implements a BrainFuck *interpreter* similar to the "official" one. # It has 30000 unsigned 8-bit cells with wrapping, going off the bounds # of the memory results in an error. (de bf (Prg) (let (P Prg S NIL D (need 30000 0) Dp D F T ) (while P (case (car P) ("+" (if F (set Dp (% (inc (car Dp) 256))))) ("-" (if F (set Dp (% (dec (car Dp) 256))))) (">" (if F (setq Dp (cdr Dp)))) ("<" (if F (setq Dp (prior Dp D)))) ("." (if F (prin (char (car Dp))))) ("," (if F (set Dp (char (read))))) ("[" (push 'S (if F (prior P Prg))) (setq F (n0 (car Dp))) ) ("]" (and (setq F (pop 'S)) (n0 (car Dp)) (setq P F) ) ) ) (pop 'P) ) ) ) # A little "Hello world! test of the interpreter." (bf (chop ">+++++++++[<++++++++>-]<.>+++++++[<++++>-]<+.+++++++..+++.[-] >++++++++[<++++>-] <.>+++++++++++[<++++++++>-]<-.--------.+++.------.--- -----.[-]>++++++++[<++++>- ]<+.[-]++++++++++." ) ) (bye)
Dynamic solution
Dynamic and unlimited. Unwraping cells. Checking syntax. <lang PicoLisp>(de brackets (Lst)
(let S NIL (make (for (I . X) Lst (case X ("[" (push 'S I)) ("]" (unless S (quit "Unbalanced '['")) (link (list (pop 'S) I)) ) ) ) (when S (quit "Unbalanced ']'")) ) ) )
(de lupbra (Lst N)
(find '((I) (or (= (car I) N) (= (cadr I) N) ) ) Lst ) )
(de brain (L)
(let (D (0) DH 1 DL 1 CH 1 CL (length L) B (brackets L) ) (loop (case (get L CH) (> (inc 'DH) (when (> DH DL) (setq D (insert DH D 0)) (inc 'DL) ) ) (< (dec 'DH) (when (< DH 1) (setq D (insert DH D 0)) (inc 'DL) (one DH) ) ) (+ (inc (nth D DH))) (- (dec (nth D DH))) (. (prin (char (get D DH)))) ("," (set (nth D DH) (char (key)))) ("[" (when (=0 (get D DH)) (setq CH (cadr (lupbra B CH))) ) ) ("]" (when (n0 (get D DH)) (setq CH (car (lupbra B CH))) ) ) ) (inc 'CH) (T (> CH CL)) ) ) )
(brain (chop ">+++++++++[<++++++++>-]<.>+++++++[<++++>-]<+.+++++++..+++.[-] >++++++++[<++++>-] <.>+++++++++++[<++++++++>-]<-.--------.+++.------.---
.[-]>++++++++[<++++>- ]<+.[-]++++++++++." ) )
(bye)</lang>
Pointless
<lang pointless>-- Code based on -- https://github.com/allisio/pointless/blob/master/lib/examples/brainfuck.ptls
output =
iterate(run, vm) |> takeUntil(isFinished) |> map(vm => vm.outVal) |> filter(notEq(None)) |> map(char) |> printElems
vm = VM {
ip = 0 dp = 0 data = zeroArray(1000) inVals = map(ord, readLines) outVal = None
}
-- "hello.bf" contains brainf*** hello world code
ops = toArray(readFile("hello.bf"))
run(vm) = vm |> clearOutput |> eval |> advance
advance(vm) = vm with $.ip += 1 isFinished(vm) = vm.ip >= length(ops) clearOutput(vm) = vm with $.outVal = None
jumps = getJumps(0, [], {})
getJumps(i, stack, jumps) = cond {
case (i == length(ops)) jumps
case (ops[i] == "[") getJumps(i + 1, [i] ++ stack, jumps)
case (ops[i] == "]") getJumps(i + 1, tail(stack), jumps with { $[i] = head(stack) $[head(stack)] = i })
else getJumps(i + 1, stack, jumps)
}
eval(vm) = cond {
case (op == ">") vm with $.dp += 1 case (op == "<") vm with $.dp -= 1 case (op == "+") vm with $.data[vm.dp] += 1 case (op == "-") vm with $.data[vm.dp] -= 1 case (op == ".") vm with $.outVal = byte
case (op == ",") vm with { $.data[vm.dp] = head(vm.inVals) $.inVals = tail(vm.inVals) }
case (op == "[") if byte != 0 then vm else (vm with $.ip = jumps[vm.ip])
case (op == "]") if byte == 0 then vm else (vm with $.ip = jumps[vm.ip])
else vm
} where {
op = ops[vm.ip] byte = vm.data[vm.dp]
}</lang>
Potion
Tape is infinite length to the right. Cells use default Potion integer type. <lang># Where `code` is a string. bf = (code) :
tape = (0) tape_pos = 0 brackets = () i = -1 while (++i < code length) : if (code(i) == ">"): if (++tape_pos == tape length): tape append(0).. elsif (code(i) == "<"): tape_pos--. elsif (code(i) == "+"): tape(tape_pos) = tape(tape_pos) + 1. elsif (code(i) == "-"): tape(tape_pos) = tape(tape_pos) - 1. elsif (code(i) == "."): tape(tape_pos) chr print. elsif (code(i) == ","): tape(tape_pos) = read at(0) ord. elsif (code(i) == "["): brackets push(i). elsif (code(i) == "]") : if (tape(tape_pos) == 0): brackets pop. else: i = brackets(-1). . .
.</lang>
Prolog
Features: Ignores comments (non brainf*** characters), Can run as command, or from file, no limit on memory.
<lang prolog>/******************************************
Starting point, call with program in atom.
- /
brain(Program) :- atom_chars(Program, Instructions), process_bf_chars(Instructions).
brain_from_file(File) :- % or from file... read_file_to_codes(File, Codes, []), maplist(char_code, Instructions, Codes), process_bf_chars(Instructions).
process_bf_chars(Instructions) :- phrase(bf_to_pl(Code), Instructions, []), Code = [C|_], instruction(C, Code, mem([], [0])), !.
/********************************************
DCG to parse the bf program into prolog form
- /
bf_to_pl([]) --> []. bf_to_pl([loop(Ins)|Next]) --> loop_start, bf_to_pl(Ins), loop_end, bf_to_pl(Next). bf_to_pl([Ins|Next]) --> bf_code(Ins), bf_to_pl(Next). bf_to_pl(Ins) --> [X], { \+ member(X, ['[',']',>,<,+,-,'.',',']) }, bf_to_pl(Ins). % skip non bf characters
loop_start --> ['[']. loop_end --> [']'].
bf_code(next_addr) --> ['>']. bf_code(prev_addr) --> ['<']. bf_code(inc_caddr) --> ['+']. bf_code(dec_caddr) --> ['-']. bf_code(out_caddr) --> ['.']. bf_code(in_caddr) --> [','].
/**********************
Instruction Processor
- /
instruction([], _, _). instruction(I, Code, Mem) :- mem_instruction(I, Mem, UpdatedMem), next_instruction(Code, NextI, NextCode), !, % cuts are to force tail recursion, so big programs will run instruction(NextI, NextCode, UpdatedMem).
% to loop, add the loop code to the start of the program then execute % when the loop has finished it will reach itself again then can retest for zero instruction(loop(LoopCode), Code, Mem) :- caddr(Mem, X), dif(X, 0), append(LoopCode, Code, [NextI|NextLoopCode]), !, instruction(NextI, [NextI|NextLoopCode], Mem). instruction(loop(_), Code, Mem) :- caddr(Mem, 0), next_instruction(Code, NextI, NextCode), !, instruction(NextI, NextCode, Mem).
% memory is stored in two parts: % 1. a list with the current address and everything after it % 2. a list with the previous memory in reverse order mem_instruction(next_addr, mem(Mb, [Caddr]), mem([Caddr|Mb], [0])). mem_instruction(next_addr, mem(Mb, [Caddr,NextAddr|Rest]), mem([Caddr|Mb], [NextAddr|Rest])). mem_instruction(prev_addr, mem([PrevAddr|RestOfPrev], Caddrs), mem(RestOfPrev, [PrevAddr|Caddrs])).
% wrap instructions at the byte boundaries as this is what most programmers expect to happen mem_instruction(inc_caddr, MemIn, MemOut) :- caddr(MemIn, 255), update_caddr(MemIn, 0, MemOut). mem_instruction(inc_caddr, MemIn, MemOut) :- caddr(MemIn, Val), succ(Val, IncVal), update_caddr(MemIn, IncVal, MemOut). mem_instruction(dec_caddr, MemIn, MemOut) :- caddr(MemIn, 0), update_caddr(MemIn, 255, MemOut). mem_instruction(dec_caddr, MemIn, MemOut) :- caddr(MemIn, Val), succ(DecVal, Val), update_caddr(MemIn, DecVal, MemOut).
% input and output mem_instruction(out_caddr, Mem, Mem) :- caddr(Mem, Val), char_code(Char, Val), write(Char). mem_instruction(in_caddr, MemIn, MemOut) :- get_single_char(Code), char_code(Char, Code), write(Char), map_input_code(Code,MappedCode), update_caddr(MemIn, MappedCode, MemOut).
% need to map the newline if it is not a proper newline character (system dependent). map_input_code(13,10) :- nl. map_input_code(C,C).
% The value at the current address caddr(mem(_, [Caddr]), Caddr). caddr(mem(_, [Caddr,_|_]), Caddr).
% The updated value at the current address update_caddr(mem(BackMem, [_]), Caddr, mem(BackMem, [Caddr])). update_caddr(mem(BackMem, [_,M|Mem]), Caddr, mem(BackMem, [Caddr,M|Mem])).
% The next instruction, and remaining code next_instruction([_], [], []). next_instruction([_,NextI|Rest], NextI, [NextI|Rest]).</lang>
- Output:
?- brain('++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.'). Hello World! true
PureBasic
Python
Racket
Brainfudge is an implementation of Brain**** in Racket. Read the tutorial to see you can integrate a new language into the Racket system. The tutorial also shows how to get IDE support from DrRacket.
As an appetizer this runs in Racket as is:
<lang racket>
- lang planet dyoo/bf
++++++[>++++++++++++<-]>. >++++++++++[>++++++++++<-]>+. +++++++..+++.>++++[>+++++++++++<-]>. <+++[>----<-]>.<<<<<+++[>+++++<-]>. >>.+++.------.--------.>>+. </lang>
Raku
(formerly Perl 6)
Rebol
Works with Rebol3 <lang Rebol> REBOL [Title: "Brainfuck interpreter"]
tape: make object! [
pos: 1 data: [0] inc: does [ data/:pos: data/:pos + 1 ] dec: does [ data/:pos: data/:pos - 1 ] advance: does [ pos: pos + 1 if (length? data) <= pos [ append data 0 ] ] devance: does [ if pos > 1 [ pos: pos - 1 ] ] get: does [ data/:pos ]
]
brainfuck: make object! [
data: string! code: "" init: func [instr] [ self/data: instr ] bracket-map: func [text] [ leftstack: [] bm: make map! [] pc: 1 for i 1 (length? text) 1 [ c: text/:i if not find "+-<>[].," c [ continue ] if c == #"[" [ append leftstack pc ] if c == #"]" & ((length? leftstack) > 0) [ left: last leftstack take/last leftstack append bm reduce [left pc] append bm reduce [pc left] ] append code c pc: pc + 1 ] return bm ] run: function [] [ pc: 0 tp: make tape [] bm: bracket-map self/data while [pc <= (length? code)] [ switch/default code/:pc [ #"+" [tp/inc] #"-" [tp/dec] #">" [tp/advance] #"<" [tp/devance] #"[" [if tp/get == 0 [ pc: bm/:pc ]] #"]" [if tp/get != 0 [ pc: bm/:pc ]] #"." [prin to-string to-char tp/get] ] [] pc: pc + 1 ] print newline ]
]
bf: make brainfuck [] bf/init input bf/run </lang>
REXX
The REXX code is original, but the BRAINF░CK program was modified from the example given in Wikipedia: [4] <lang rexx>/*REXX program implements the Brainf*ck (self─censored) language. */ @.=0 /*initialize the infinite "tape". */ p =0 /*the "tape" cell pointer. */ ! =0 /* ! is the instruction pointer (IP).*/ parse arg $ /*allow user to specify a BrainF*ck pgm*/
/* ┌──◄── No program? Then use default;*/
if $= then $=, /* ↓ it displays: Hello, World! */
"++++++++++ initialize cell #0 to 10; then loop: ", "[ > +++++++ add 7 to cell #1; final result: 70 ", " > ++++++++++ add 10 to cell #2; final result: 100 ", " > +++ add 3 to cell #3; final result 30 ", " > + add 1 to cell #4; final result 10 ", " <<<< - ] decrement cell #0 ", "> ++ . display 'H' which is ASCII 72 (decimal) ", "> + . display 'e' which is ASCII 101 (decimal) ", "+++++++ .. display 'll' which is ASCII 108 (decimal) {2}", "+++ . display 'o' which is ASCII 111 (decimal) ", "> ++ . display ' ' which is ASCII 32 (decimal) ", "<< +++++++++++++++ . display 'W' which is ASCII 87 (decimal) ", "> . display 'o' which is ASCII 111 (decimal) ", "+++ . display 'r' which is ASCII 114 (decimal) ", "------ . display 'l' which is ASCII 108 (decimal) ", "-------- . display 'd' which is ASCII 100 (decimal) ", "> + . display '!' which is ASCII 33 (decimal) " /* [↑] note the Brainf*ck comments.*/ do !=1 while !\==0 & !<=length($) /*keep executing BF as long as IP ¬ 0*/ parse var $ =(!) x +1 /*obtain a Brainf*ck instruction (x),*/ /*···it's the same as x=substr($,!,1) */ select /*examine the current instruction. */ when x=='+' then @.p=@.p + 1 /*increment the "tape" cell by 1 */ when x=='-' then @.p=@.p - 1 /*decrement " " " " " */ when x=='>' then p= p + 1 /*increment " instruction ptr " " */ when x=='<' then p= p - 1 /*decrement " " " " " */ when x=='[' then != forward() /*go forward to ]+1 if @.P = 0. */ when x==']' then !=backward() /* " backward " [+1 " " ¬ " */ when x== . then call charout , d2c(@.p) /*display a "tape" cell to terminal. */ when x==',' then do; say 'input a value:'; parse pull @.p; end otherwise iterate end /*select*/ end /*forever*/
exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ forward: if @.p\==0 then return !; c=1 /*C: ◄─── is the [ nested counter.*/
do k=!+1 to length($); ?=substr($, k, 1) if ?=='[' then do; c=c+1; iterate; end if ?==']' then do; c=c-1; if c==0 then leave; end end /*k*/ return k
/*──────────────────────────────────────────────────────────────────────────────────────*/ backward: if @.p==0 then return !; c=1 /*C: ◄─── is the ] nested counter.*/
do k=!-1 to 1 by -1; ?=substr($, k, 1) if ?==']' then do; c=c+1; iterate; end if ?=='[' then do; c=c-1; if c==0 then return k+1; end end /*k*/ return k</lang>
output when using the default program as input:
Hello World!
Ruby
Rust
<lang rust>use std::collections::HashMap; use std::env; use std::fs::File; use std::io::prelude::*; use std::io::stdin; use std::num::Wrapping;
fn main() {
let args: Vec<_> = env::args().collect(); if args.len() < 2 { println!("Usage: {} [path] (--debug)", args[0]); return; }
let src: Vec<char> = { let mut buf = String::new(); match File::open(&args[1]) { Ok(mut f) => { f.read_to_string(&mut buf).unwrap(); } Err(e) => { println!("Error opening '{}': {}", args[1], e); return; } }
buf.chars().collect() };
// Launch options let debug = args.contains(&"--debug".to_owned());
// One pass to find bracket pairs. let brackets: HashMap<usize, usize> = { let mut m = HashMap::new(); let mut scope_stack = Vec::new(); for (idx, ch) in src.iter().enumerate() { match ch { &'[' => { scope_stack.push(idx); } &']' => { m.insert(scope_stack.pop().unwrap(), idx); } _ => { /* ignore */ } } }
m };
let mut pc: usize = 0; // Program counter let mut mem: [Wrapping<u8>;5000] = [Wrapping(0);5000]; // Program cemory let mut ptr: usize = 0; // Pointer let mut stack: Vec<usize> = Vec::new(); // Bracket stack
let stdin_ = stdin(); let mut reader = stdin_.lock().bytes(); while pc < src.len() { let Wrapping(val) = mem[ptr];
if debug { println!("(BFDB) PC: {:04} \tPTR: {:04} \t$PTR: {:03} \tSTACK_DEPTH: {} \tSYMBOL: {}", pc, ptr, val, stack.len(), src[pc]); }
const ONE: Wrapping<u8> = Wrapping(1); match src[pc] { '>' => { ptr += 1; } '<' => { ptr -= 1; }
'+' => { mem[ptr] = mem[ptr] + ONE; } '-' => { mem[ptr] = mem[ptr] - ONE; }
'[' => { if val == 0 { pc = brackets[&pc]; } else { stack.push(pc); } } ']' => { let matching_bracket = stack.pop().unwrap(); if val != 0 { pc = matching_bracket - 1; } }
'.' => { if debug { println!("(BFDB) STDOUT: '{}'", val as char); // Intercept output } else { print!("{}", val as char); } } ',' => { mem[ptr] = Wrapping(reader.next().unwrap().unwrap()); }
_ => { /* ignore */ } }
pc += 1; }
}</lang>
Scala
<lang Scala> import scala.annotation._
trait Func[T] {
val zero: T def inc(t: T): T def dec(t: T): T def in: T def out(t: T): Unit
}
object ByteFunc extends Func[Byte] {
override val zero: Byte = 0 override def inc(t: Byte) = ((t + 1) & 0xFF).toByte override def dec(t: Byte) = ((t - 1) & 0xFF).toByte override def in: Byte = readByte override def out(t: Byte) { print(t.toChar) }
}
case class Tape[T](left: List[T], cell: T, right: List[T])(implicit func: Func[T]) {
private def headOf(list:List[T]) = if (list.isEmpty) func.zero else list.head private def tailOf(list:List[T]) = if (list.isEmpty) Nil else list.tail def isZero = cell == func.zero def execute(ch: Char) = (ch: @switch) match { case '+' => copy(cell = func.inc(cell)) case '-' => copy(cell = func.dec(cell)) case '<' => Tape(tailOf(left), headOf(left), cell :: right) case '>' => Tape(cell :: left, headOf(right), tailOf(right)) case '.' => func.out(cell); this case ',' => copy(cell = func.in) case '[' | ']' => this case _ => error("Unexpected token: " + ch) }
}
object Tape {
def empty[T](func: Func[T]) = Tape(Nil, func.zero, Nil)(func)
}
class Brainfuck[T](func:Func[T]) {
def execute(p: String) { val prog = p.replaceAll("[^\\+\\-\\[\\]\\.\\,\\>\\<]", "")
@tailrec def braceMatcher(pos: Int, stack: List[Int], o2c: Map[Int, Int]): Map[Int,Int] = if(pos == prog.length) o2c else (prog(pos): @switch) match { case '[' => braceMatcher(pos + 1, pos :: stack, o2c) case ']' => braceMatcher(pos + 1, stack.tail, o2c + (stack.head -> pos)) case _ => braceMatcher(pos + 1, stack, o2c) }
val open2close = braceMatcher(0, Nil, Map()) val close2open = open2close.map(_.swap)
@tailrec def ex(pos:Int, tape:Tape[T]): Unit = if(pos < prog.length) ex((prog(pos): @switch) match { case '[' if tape.isZero => open2close(pos) case ']' if ! tape.isZero => close2open(pos) case _ => pos + 1 }, tape.execute(prog(pos)))
println("---running---") ex(0, Tape.empty(func)) println("\n---done---") }
} </lang>
Scheme
Seed7
<lang seed7>$ include "seed7_05.s7i";
const proc: brainF (in string: source, inout file: input, inout file: output) is func
local var array char: memory is 100000 times '\0;'; var integer: dataPointer is 50000; var integer: instructionPointer is 1; var integer: nestingLevel is 0; begin while instructionPointer <= length(source) do case source[instructionPointer] of when {'>'}: incr(dataPointer); when {'<'}: decr(dataPointer); when {'+'}: incr(memory[dataPointer]); when {'-'}: decr(memory[dataPointer]); when {'.'}: write(output, memory[dataPointer]); when {','}: memory[dataPointer] := getc(input); when {'['}: # Forward if zero at dataPointer if memory[dataPointer] = '\0;' then nestingLevel := 1; repeat incr(instructionPointer); case source[instructionPointer] of when {'['}: incr(nestingLevel); when {']'}: decr(nestingLevel); end case; until nestingLevel = 0; end if; when {']'}: # Backward if non-zero at dataPointer if memory[dataPointer] <> '\0;' then nestingLevel := 1; repeat decr(instructionPointer); case source[instructionPointer] of when {'['}: decr(nestingLevel); when {']'}: incr(nestingLevel); end case; until nestingLevel = 0; end if; end case; incr(instructionPointer); end while; end func;
const proc: brainF (in string: source) is func
begin brainF(source, IN, OUT); end func;
const proc: main is func
begin brainF("++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>."); end func;</lang>
- Output:
Hello World!
Original source [5].
Sidef
<lang ruby>define tape_length = 50_000; define eof_val = -1; define unbalanced_exit_code = 1;
var cmd = 0; var cell = 0; var code = []; var loops = []; var tape = tape_length.of(0);
func get_input {
static input_buffer = []; input_buffer.len || (input_buffer = ((STDIN.readline \\ return eof_val).chomp.chars.map{.ord})); input_buffer.shift \\ eof_val;
}
func jump {
var depth = 0; while (depth >= 0) { ++cmd < code.len || Sys.exit(unbalanced_exit_code); if (code[cmd] == '[') { ++depth; } elsif (code[cmd] == ']') { --depth; } }
}
var commands = Hash.new(
'>' => { ++cell }, '<' => { --cell }, '+' => { ++tape[cell] }, '-' => { --tape[cell] }, '.' => { tape[cell].chr.print }, ',' => { tape[cell] = get_input() }, '[' => { tape[cell] ? loops.append(cmd) : jump() }, ']' => { cmd = (loops.pop - 1) },
);
STDOUT.autoflush(1); code = ARGF.slurp.chars.grep {|c| commands.exists(c)}; var code_len = code.len;
while (cmd < code_len) {
commands{code[cmd]}.run; cmd++;
}</lang>
Standard ML
Implementation in Standard ML.
Swift
<lang Swift>import Foundation
let valids = [">", "<", "+", "-", ".", ",", "[", "]"] as Set<Character> var ip = 0 var dp = 0 var data = [UInt8](count: 30_000, repeatedValue: 0)
let input = Process.arguments
if input.count != 2 {
fatalError("Need one input file")
}
let infile: String!
do {
infile = try String(contentsOfFile: input[1], encoding: NSUTF8StringEncoding) ?? ""
} catch let err {
infile = ""
}
var program = ""
// remove invalid chars for c in infile.characters {
if valids.contains(c) { program += String(c) }
}
let numChars = program.characters.count
if numChars == 0 {
fatalError("Error reading file")
}
func increaseInstructionPointer() {
ip += 1
}
func executeInstruction(ins: Character) {
switch ins { case ">": dp += 1 increaseInstructionPointer() case "<": dp -= 1 increaseInstructionPointer() case "+": data[dp] = data[dp] &+ 1 increaseInstructionPointer() case "-": data[dp] = data[dp] &- 1 increaseInstructionPointer() case ".": print(Character(UnicodeScalar(data[dp])), terminator: "") increaseInstructionPointer() case ",": handleIn() increaseInstructionPointer() case "[": handleOpenBracket() case "]": handleClosedBracket() default: fatalError("What") }
}
func handleIn() {
let input = NSFileHandle.fileHandleWithStandardInput() let bytes = input.availableData.bytes let buf = unsafeBitCast(UnsafeBufferPointer(start: bytes, count: 1), UnsafeBufferPointer<UInt8>.self) data[dp] = buf[0]
}
func handleOpenBracket() {
if data[dp] == 0 { var i = 1 while i > 0 { ip += 1 let ins = program[program.startIndex.advancedBy(ip)] if ins == "[" { i += 1 } else if ins == "]" { i -= 1 } } } else { increaseInstructionPointer() }
}
func handleClosedBracket() {
if data[dp] != 0 { var i = 1 while i > 0 { ip -= 1 let ins = program[program.startIndex.advancedBy(ip)] if ins == "[" { i -= 1 } else if ins == "]" { i += 1 } } } else { increaseInstructionPointer() }
}
func tick() {
let ins = program[program.startIndex.advancedBy(ip)] if valids.contains(ins) { executeInstruction(ins) } else { increaseInstructionPointer() }
}
while ip != numChars {
tick()
}</lang>
Tcl
TI-83 BASIC
Implementation in TI-83 BASIC.
TI-89 BASIC
Implementation in TI-89 Basic.
UNIX Shell
<lang bash>#!/usr/bin/env bash
- BrainF*** interpreter in bash
if (( ! $# )); then
printf >&2 'Usage: %s program-file\n' "$0" exit 1
fi
- load the program
exec 3<"$1" program=() while IFS= read -r line <&3; do
mapfile -t instr < <(tr -cd '[]<>.,+-' <<<"$line" | sed $'s/./&\\\n/g') program+=("${instr[@]}")
done exec 3<&-
- parse loops
loops=() matches=() for pc in "${!program[@]}"; do
instr=${program[pc]} if [[ $instr == '[' ]]; then loops=("$pc" "${loops[@]}") elif [[ $instr == ']' ]]; then matches[$pc]=${loops[0]} matches[${loops[0]}]=$pc loops=(${loops[@]:1}) fi
done
- execute program
memory=(0) mp=0 pc=0 while (( pc < ${#program[@]} )); do
instr=${program[pc]} (( pc+=1 )) mem=${memory[mp]} case "$instr" in '[') if (( ! mem )); then (( pc=${matches[pc-1]}+1 )); fi;; ']') if (( mem )); then (( pc=${matches[pc-1]}+1 )); fi;; +) memory[mp]=$(( (mem + 1) % 256 ));; -) memory[mp]=$(( (mem - 1) % 256 ));; '>') (( mp+=1 )); if (( mp >= ${#memory[@]} )); then memory+=(0); fi;; '<') (( mp-=1 )); if (( mp < 0 )); then memory=(0 "${memory[@]}"); mp=0; fi;; .) printf %b $(printf '\\%03o' "$mem");; ,) read -n1 c; memory[mp]=$(LC_CTYPE=C printf '%d' "'$c");; esac
done</lang>
Sample run:
$ bash bf.bash <(echo '>++++++++[<+++++++++>-]<.>>+>+>++>[-]+<[>[->+<<++++>]<<]>.+++++++..+++.>>+++++++.<<<[[-]<[-]>]<+++++++++++++++.>>.+++.------.--------.>>+.>++++.')
- Output:
Hello World!
VBScript
<lang vb>'Execute BrainFuck 'VBScript Implementation
'The Main Interpreter Function BFInpt(s, sp, d, dp, i, ip, o)
While sp < Len(s) Select Case Mid(s, sp + 1, 1) Case "+" newd = Asc(d(dp)) + 1 If newd > 255 Then newd = newd Mod 256 'To take account of values over 255 d(dp) = Chr(newd) Case "-" newd = Asc(d(dp)) - 1 If newd < 0 Then newd = (newd Mod 256) + 256 'To take account of negative values d(dp) = Chr(newd) Case ">" dp = dp + 1 If dp > UBound(d) Then ReDim Preserve d(UBound(d) + 1) d(dp) = Chr(0) End If Case "<" dp = dp - 1 Case "." o = o & d(dp) Case "," If ip = Len(i) Then d(dp) = Chr(0) Else ip = ip + 1 : d(dp) = Mid(i, ip, 1) Case "[" If Asc(d(dp)) = 0 Then bracket = 1 While bracket And sp < Len(s) sp = sp + 1 If Mid(s, sp + 1, 1) = "[" Then bracket = bracket + 1 ElseIf Mid(s, sp + 1, 1) = "]" Then bracket = bracket - 1 End If WEnd Else pos = sp - 1 sp = sp + 1 If BFInpt(s, sp, d, dp, i, ip, o) Then sp = pos End If Case "]" BFInpt = Asc(d(dp)) <> 0 Exit Function End Select sp = sp + 1 WEnd
End Function
'This Prepares the Intepreter Function BFuck(source, input)
Dim data() : ReDim data(0) data(0) = Chr(0) DataPtr = 0 SrcPtr = 0 InputPtr = 0 output = ""
BFInpt source , SrcPtr , _ data , DataPtr , _ input , InputPtr , _ output BFuck = output
End Function
'Sample Run
'The input is a string. The first character will be scanned by the first comma
'in the code, the next character will be scanned by the next comma, and so on.
code = ">++++++++[<+++++++++>-]<.>>+>+>++>[-]+<[>[->+<<++++>]<<]>.+++++++..+++.>" & _
">+++++++.<<<[[-]<[-]>]<+++++++++++++++.>>.+++.------.--------.>>+.>++++."
inpstr = "" WScript.StdOut.Write BFuck(code, inpstr)</lang>
- Output:
C:\>cscript /nologo brainf.vbs Hello world! C:\>
Wren
<lang ecmascript>import "io" for Stdin
class Brainf__k {
construct new(prog, memSize) { _prog = prog _memSize = memSize _mem = List.filled(memSize, 0) _ip = 0 _dp = 0 }
memVal_ { (_dp >= 0 && _dp < _memSize) ? _mem[_dp] : 0 }
execute() { while (_ip < _prog.count) { var cmd = _prog[_ip] _ip = _ip + 1 if (cmd == ">") { _dp = _dp + 1 } else if (cmd == "<") { _dp = _dp - 1 } else if (cmd == "+") { _mem[_dp] = memVal_ + 1 } else if (cmd == "-") { _mem[_dp] = memVal_ - 1 } else if (cmd == ",") { _mem[_dp] = Stdin.readByte() } else if (cmd == ".") { System.write(String.fromByte(memVal_)) } else if (cmd == "[") { handleLoopStart_() } else if (cmd == "]") { handleLoopEnd_() } } }
handleLoopStart_() { if (memVal_ != 0) return var depth = 1 while (_ip < _prog.count) { var cmd = _prog[_ip] _ip = _ip + 1 if (cmd == "[") { depth = depth + 1 } else if (cmd == "]") { depth = depth - 1 if (depth == 0) return } } Fiber.abort("Could not find matching end bracket.") }
handleLoopEnd_() { var depth = 0 while (_ip >= 0) { _ip = _ip - 1 var cmd = _prog[_ip] if (cmd == "]") { depth = depth + 1 } else if (cmd == "[") { depth = depth - 1 if (depth == 0) return } } Fiber.abort("Could not find matching start bracket.") }
}
var prog = "++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>." Brainf__k.new(prog, 10).execute()</lang>
- Output:
Hello World!
x86 Assembly
zkl
<lang zkl>fcn bf(pgm,input=""){ pgm=pgm.text; // handle both String and Data
const CELLS=0d30_000; if(Void==pgm.span("[","]")){ println("Mismatched brackets"); return(); } fcn(code,z,jmpTable){ // build jump table (for [ & ]) if(span:=code.span("[","]")){
a,b:=span; b+=a-1; jmpTable[a+z]=b+z; jmpTable[b+z]=a+z; self.fcn(code[a+1,b-a-1],z+a+1,jmpTable); self.fcn(code[b+1,*],z+b+1,jmpTable);
} }(pgm,0,jmpTable:=Dictionary());
tape:=CELLS.pump(Data(CELLS,Int),0); ip:=dp:=0; input=input.walker(); try{ while(1){
switch(pgm[ip]){ case(">"){ dp+=1 } case("<"){ dp-=1 } case("+"){ tape[dp]=tape[dp]+1 } case("-"){ tape[dp]=tape[dp]-1 } case("."){ tape[dp].toChar().print() } case(","){ c:=input._next(); tape[dp]=(c and input.value or 0); } case("["){ if(0==tape[dp]){ ip=jmpTable[ip] }} case("]"){ if(tape[dp]) { ip=jmpTable[ip] }} } ip+=1;
} // while }catch(IndexError){} // read past end of tape == end of program
}</lang> <lang zkl> // print Hello World! bf("++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++.."
"+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.");
// print @
bf(">>++++[<++++[<++++>-]>-]<<.[-]++++++++++.");
// read 3 characters, inc by 1 and print: "abc"-->"bcd"
bf(",>,>,><<<[+.>]","abc"); println();
bf(",>++++++[<-------->-],[<+>-]<.","23"); println(); // add two digits
// "Enter your name:", prints name backwards
bf(">+++++++++++++++++++++++++++++++++++++++++"
"++++++++++++++++++++++++++++.++++++++++++++" "+++++++++++++++++++++++++++.++++++.-------------" "--.+++++++++++++.>++++++++++++++++++++++++++" "++++++.<+++++++.----------.++++++.---.>.<----.----------" "---.++++++++++++.--------.-----------------------------------" "--------.>.<>>>+[>,----------]++++++++++.<[+++++++++" "+.<][<]","Sam Iam\n");
// word count
bf(File("wc.b").read(),"This\n is a test");
// rot13
bf(File("rot13.b").read(),"This is a test 123");</lang>
- Output:
Hello World! @ bcd 5 Enter your name: maI maS 1 4 15 Guvf vf n grfg 123^CCntl C noted
The rot13 program is from the Wikipedia and has an infinite loop as it expects a different EoF than I use.
The word count program is:
>>>+>>>>>+>>+>>+[<<],[ -[-[-[-[-[-[-[-[<+>-[>+<-[>-<-[-[-[<++[<++++++>-]< [>>[-<]<[>]<-]>>[<+>-[<->[-]]]]]]]]]]]]]]]] <[-<<[-]+>]<<[>>>>>>+<<<<<<-]>[>]>>>>>>>+>[ <+[ >+++++++++<-[>-<-]++>[<+++++++>-[<->-]+[+>>>>>>]] <[>+<-]>[>>>>>++>[-]]+< ]>[-<<<<<<]>>>> ], ]+<++>>>[[+++++>>>>>>]<+>+[[<++++++++>-]<.<<<<<]>>>>>>>>] [Counts lines, words, bytes. Assumes no-change-on-EOF or EOF->0. Daniel B Cristofani (cristofdathevanetdotcom) http://www.hevanet.com/cristofd/brainfuck/]
ZX Spectrum Basic
The bracket loop could be accelerated to prevent searching the string every time, but it runs. <lang zxbasic>10 GO SUB 1000 20 LET e=LEN p$ 30 LET a$=p$(ip) 40 IF a$=">" THEN LET dp=dp+1 50 IF a$="<" THEN LET dp=dp-1 60 IF a$="+" THEN LET d(dp)=d(dp)+1 70 IF a$="-" THEN LET d(dp)=d(dp)-1 80 IF a$="." THEN PRINT CHR$ d(dp); 90 IF a$="," THEN INPUT d(dp) 100 IF a$="[" THEN GO SUB 500 110 IF a$="]" THEN LET bp=bp-1: IF d(dp)<>0 THEN LET ip=b(bp)-1 120 LET ip=ip+1 130 IF ip>e THEN PRINT "eof": STOP 140 GO TO 30
499 REM match close 500 LET bc=1: REM bracket counter 510 FOR x=ip+1 TO e 520 IF p$(x)="[" THEN LET bc=bc+1 530 IF p$(x)="]" THEN LET bc=bc-1 540 IF bc=0 THEN LET b(bp)=ip: LET be=x: LET x=e: REM bc will be 0 once all the subnests have been counted over 550 IF bc=0 AND d(dp)=0 THEN LET ip=be: LET bp=bp-1 560 NEXT x 570 LET bp=bp+1 580 RETURN
999 REM initialisation 1000 DIM d(100): REM data stack 1010 LET dp=1: REM data pointer 1020 LET ip=1: REM instruction pointer 1030 DIM b(30): REM bracket stack 1040 LET bp=1: REM bracket pointer 1050 LET p$="++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>+++++.": REM program, marginally modified from Wikipedia; outputs CHR$ 13 at the end instead of CHR$ 10 as ZX Spectrum Basic handles the carriage return better than the line feed 1060 RETURN</lang>
- Output:
Hello World! eof 9 STOP statement, 130:3
- Programming Tasks
- Solutions by Programming Task
- Compilers and Interpreters
- Implementations
- Brainf*** Implementations
- Brainf*** related
- 11l
- 68000 Assembly
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- Ada
- Agena
- ALGOL 68
- AppleScript
- Arturo
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- GUISS/Omit