Dynamic variable names: Difference between revisions
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pad swap 9 + evaluate</lang> |
pad swap 9 + evaluate</lang> |
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Of course, it is easier for the user to simply type VARIABLE ''name'' at the Forth console. |
Of course, it is easier for the user to simply type VARIABLE ''name'' at the Forth console. |
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=={{header|FreeBASIC}}== |
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FreeBASIC is a statically typed, compiled language and so it is not possible to create new variables, dynamically, at run time. However, you can make it look to the user like you are doing so with code such as the following. Ideally, a 'map' should be used for an exercise such as this but, as there isn't one built into FB, I've used a dynamic array instead which is searched linearly for the variable name. |
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<lang freebasic>' FB 1.05.0 Win64 |
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Type DynamicVariable |
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As String name |
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As String value |
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End Type |
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Function FindVariableIndex(a() as DynamicVariable, v as String, nElements As Integer) As Integer |
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v = LCase(Trim(v)) |
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For i As Integer = 1 To nElements |
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If a(i).name = v Then Return i |
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Next |
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Return 0 |
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End Function |
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Dim As Integer n, index |
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Dim As String v |
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Cls |
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Do |
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Input "How many variables do you want to create (max 5) "; n |
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Loop Until n > 0 AndAlso n < 6 |
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Dim a(1 To n) As DynamicVariable |
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Print |
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Print "OK, enter the variable names and their values, below" |
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For i As Integer = 1 to n |
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Print |
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Print " Variable"; i |
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Input " Name : ", a(i).name |
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a(i).name = LCase(Trim(a(i).name)) ' variable names are not case sensitive in FB |
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If i > 0 Then |
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index = FindVariableIndex(a(), a(i).name, i - 1) |
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If index > 0 Then |
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Print " Sorry, you've already created a variable of that name, try again" |
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i -= 1 |
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Continue For |
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End If |
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End If |
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Input " Value : ", a(i).value |
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a(i).value = LCase(Trim(a(i).value)) |
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Next |
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Print |
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Print "Press q to quit" |
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Do |
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Print |
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Input "Which variable do you want to inspect "; v |
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If v = "q" OrElse v = "Q" Then Exit Do |
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index = FindVariableIndex(a(), v, n) |
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If index = 0 Then |
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Print "Sorry there's no variable of that name, try again" |
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Else |
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Print "It's value is "; a(index).value |
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End If |
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Loop |
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End</lang> |
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Sample input/output : |
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{{out}} |
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<pre> |
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How many variables do you want to create (max 5) ? 3 |
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OK, enter the variable names and their values, below |
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Variable 1 |
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Name : a |
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Value : 1 |
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Variable 2 |
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Name : b |
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Value : 2 |
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Variable 3 |
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Name : b |
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Sorry, you've already created a variable of that name, try again |
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Variable 3 |
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Name : c |
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Value : 4 |
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Press q to quit |
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Which variable do you want to inspect ? b |
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It's value is 2 |
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Which variable do you want to inspect ? c |
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It's value is 4 |
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Which variable do you want to inspect ? a |
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It's value is 1 |
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Which variable do you want to inspect ? q |
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</pre> |
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=={{header|GAP}}== |
=={{header|GAP}}== |
Revision as of 19:27, 19 October 2016
You are encouraged to solve this task according to the task description, using any language you may know.
- Task
Create a variable with a user-defined name.
The variable name should not be written in the program text, but should be taken from the user dynamically.
- See also
- Eval in environment is a similar task.
AutoHotkey
<lang AutoHotkey>InputBox, Dynamic, Variable Name %Dynamic% = hello ListVars MsgBox % %dynamic% ; says hello</lang>
BASIC
,
<lang basic>10 INPUT "Enter a variable name", v$ 20 KEYIN "LET "+v$+"=42"</lang>
Batch File
<lang DOS>@echo off setlocal enableDelayedExpansion
set /p "name=Enter a variable name: " set /p "value=Enter a value: "
- Create the variable and set its value
set "%name%=%value%"
- Display the value without delayed expansion
call echo %name%=%%%name%%%
- Display the value using delayed expansion
echo %name%=!%name%!</lang>
BBC BASIC
<lang bbcbasic> INPUT "Enter a variable name: " name$
INPUT "Enter a numeric value: " numeric$ dummy% = EVAL("FNassign("+name$+","+numeric$+")") PRINT "Variable " name$ " now has the value "; EVAL(name$) END DEF FNassign(RETURN n, v) : n = v : = 0</lang>
Bracmat
<lang bracmat>( put$"Enter a variable name: " & get$:?name & whl
' ( put$"Enter a numeric value: " & get$:?numeric:~# )
& !numeric:?!name & put$(str$("Variable " !name " now has the value " !!name \n)) );</lang>
Clojure
<lang clojure>(eval `(def ~(symbol (read)) 42))</lang>
Common Lisp
The short answer is this: <lang lisp> (setq var-name (read)) ; reads a name into var-name (set var-name 1) ; assigns the value 1 to a variable named as entered by the user </lang>
The academic answer is this:
In Common Lisp, symbol objects name variables; symbols are produced from strings by way of read
(general syntax) or intern
(specificially retrieving or making a symbol).
Symbols are grouped into packages — roughly namespaces — and any time symbols are created at runtime it is usually good to explicitly specify what package they are created in, outside of user/developer tools for working from the REPL (interactive mode) where the current package *package*
is appropriate.
Within the standard, every variable is either lexical or special (dynamic scope). There is no global lexical environment, so in order to "create a variable", we must either create our own mechanism to remember it for lexical binding in a later evaluation, or create a special variable. It is unspecified what happens when a symbol not lexically bound or declared special is used as a variable.
Every symbol has a value slot — a field which, roughly, contains its current value considered as a special variable.
Therefore, there are two parts to dynamically creating a variable: we must declare it special, and give it a value. The first part is accomplished by the proclaim
function for making declarations at run-time. The second part is simply assigning to the value slot.
<lang lisp>(defun rc-create-variable (name initial-value)
"Create a global variable whose name is NAME in the current package and which is bound to INITIAL-VALUE." (let ((symbol (intern name))) (proclaim `(special ,symbol)) (setf (symbol-value symbol) initial-value) symbol))</lang>
<lang lisp>CL-USER> (rc-create-variable "GREETING" "hello") GREETING
CL-USER> (print greeting) "hello"</lang> Things to note:
- Once a symbol has been declared special, it cannot be used as a lexical variable. Because of this potentially-surprising behavior, it is conventional to give all symbols naming special variables distinguished names, typically by asterisks as in
*greeting*
, so that lexical variables will not accidentally be given those names.
- Some implementations do, to some extent, support global non-special variables; in these, because of the preceding problem, it is better to simply set the value slot and not proclaim it special. However, this may provoke undefined-variable warnings since the compiler or interpreter has no information with which to know the symbol is intended to be a variable.
- Common Lisp, by default, is case-insensitive; however it accomplishes this by canonicalizing read input to uppercase; there is syntax to denote a lower or mixed-case symbol name,
|Foo|
orF\o\o
.intern
does not go through the input path (reader), so we must provide the name in uppercase to make an "ordinary" variable name.
Déjà Vu
In Déjà Vu, variable names are idents, which are completely separate from strings, and cannot easily be created from them. The way around that is to invoke the compiler: <lang dejavu>local :var-name !run-blob !compile-string dup concat( ":" !prompt "Enter a variable name: " ) local var-name 42
- Assuming the user types THISISWEIRD, otherwise this'll error
!. THISISWEIRD</lang>
- Output:
Enter a variable name: THISISWEIRD 42
E
In E, there are no global variables, and there is no modification of the local (lexical) environment. However, it is possible to construct a program which binds any given variable name. <lang e>def makeNounExpr := <elang:evm.makeNounExpr>
def dynVarName(name) {
def variable := makeNounExpr(null, name, null)
return e`{ def a := 1 def b := 2 def c := 3 { def $variable := "BOO!" [a, b, c] } }`.eval(safeScope)
}
? dynVarName("foo")
- value: [1, 2, 3]
? dynVarName("b")
- value: [1, "BOO!", 3]
? dynVarName("c")
- value: [1, 2, "BOO!"]</lang>
It is also possible to capture the environment object resulting from the evaluation of the constructed program and use it later; this is done by bindX
in Eval in environment#E (except for the program being constant, which is independent).
Elena
Dynamic variables are not supported by the language. But it is possible to set a dynamic property. <lang elena>#import system.
- import system'dynamic.
- import extensions.
- class TestClass
{
#field theVariables. #constructor new [ theVariables := DynamicStruct new. ] #method eval [ #var(type:subject) varRef := Signature new &literal:(console write:"Enter the variable name:" readLine). theVariables::varRef set:42. #var v := theVariables::varRef get. console writeLine:(varRef name):"=":(theVariables::varRef get). ]
}
- symbol program = TestClass new.</lang>
Emacs Lisp
A variable is a symbol. A name can be read from the user as a string and interned to a symbol.
<lang Lisp>(set (intern (read-string "Enter variable name: ")) 123)</lang>
This example deliberately doesn't use any temporary variables so their names won't clash with what the user might enter. A set
like this hits any let
dynamic binding or buffer-local setting in the usual way.
Erlang
This task uses functions from Runtime evaluation. <lang Erlang> -module( dynamic_variable_names ).
-export( [task/0] ).
task() ->
{ok,[Variable_name]} = io:fread( "Variable name? ", "~a" ), Form = runtime_evaluation:form_from_string( erlang:atom_to_list(Variable_name) ++ "." ), io:fwrite( "~p has value ~p~n", [Variable_name, runtime_evaluation:evaluate_form(Form, {Variable_name, 42})] ).
</lang>
- Output:
12> dynamic_variable_names:task(). Variable name? Asd 'Asd' has value 42
Forth
<lang forth>s" VARIABLE " pad swap move ." Variable name: " pad 9 + 80 accept pad swap 9 + evaluate</lang> Of course, it is easier for the user to simply type VARIABLE name at the Forth console.
FreeBASIC
FreeBASIC is a statically typed, compiled language and so it is not possible to create new variables, dynamically, at run time. However, you can make it look to the user like you are doing so with code such as the following. Ideally, a 'map' should be used for an exercise such as this but, as there isn't one built into FB, I've used a dynamic array instead which is searched linearly for the variable name.
<lang freebasic>' FB 1.05.0 Win64
Type DynamicVariable
As String name As String value
End Type
Function FindVariableIndex(a() as DynamicVariable, v as String, nElements As Integer) As Integer
v = LCase(Trim(v)) For i As Integer = 1 To nElements If a(i).name = v Then Return i Next Return 0
End Function
Dim As Integer n, index Dim As String v Cls
Do
Input "How many variables do you want to create (max 5) "; n
Loop Until n > 0 AndAlso n < 6
Dim a(1 To n) As DynamicVariable Print Print "OK, enter the variable names and their values, below"
For i As Integer = 1 to n
Print Print " Variable"; i Input " Name : ", a(i).name a(i).name = LCase(Trim(a(i).name)) ' variable names are not case sensitive in FB If i > 0 Then index = FindVariableIndex(a(), a(i).name, i - 1) If index > 0 Then Print " Sorry, you've already created a variable of that name, try again" i -= 1 Continue For End If End If Input " Value : ", a(i).value a(i).value = LCase(Trim(a(i).value))
Next
Print Print "Press q to quit" Do
Print Input "Which variable do you want to inspect "; v If v = "q" OrElse v = "Q" Then Exit Do index = FindVariableIndex(a(), v, n) If index = 0 Then Print "Sorry there's no variable of that name, try again" Else Print "It's value is "; a(index).value End If
Loop End</lang>
Sample input/output :
- Output:
How many variables do you want to create (max 5) ? 3 OK, enter the variable names and their values, below Variable 1 Name : a Value : 1 Variable 2 Name : b Value : 2 Variable 3 Name : b Sorry, you've already created a variable of that name, try again Variable 3 Name : c Value : 4 Press q to quit Which variable do you want to inspect ? b It's value is 2 Which variable do you want to inspect ? c It's value is 4 Which variable do you want to inspect ? a It's value is 1 Which variable do you want to inspect ? q
GAP
<lang gap># As is, will not work if val is a String Assign := function(var, val) Read(InputTextString(Concatenation(var, " := ", String(val), ";"))); end;</lang>
Genyris
The intern function creates a symbol from an arbitrary string. Defvar creates a binding. Weird symbols are quoted with pipe characters. <lang genyris>defvar (intern 'This is not a pipe.') 42 define |<weird>| 2009</lang>
Groovy
Solution: <lang groovy>def varname = 'foo' def value = 42
new GroovyShell(this.binding).evaluate("${varname} = ${value}")
assert foo == 42</lang>
Haskell
<lang haskell>data Var a = Var String a deriving Show main = do
putStrLn "please enter you variable name" vName <- getLine let var = Var vName 42 putStrLn $ "this is your variable: " ++ show var</lang>
Icon and Unicon
<lang Icon>procedure main(arglist) if *arglist = 0 then stop("Provide the names of variables in the argument list") &dump := 1 # dump program state information and variables after run every variable(!arglist) := 1 # set each user specified variable name in arglist to 1 end</lang> Note: that Unicon extends variable to allow access to variables in other co-expressions and in calling procedures
J
This code was written for J6.02. In J8.04 you will need to replace require'misc' with require'general/misc/prompt'
<lang j>require 'misc' (prompt 'Enter variable name: ')=: 0</lang>
For example: <lang j> require 'misc'
(prompt 'Enter variable name: ')=: 0
Enter variable name: FOO
FOO
0</lang> Or, if the name is defined in the variable 'userDefined' <lang j> userDefined=: 'BAR'
(userDefined)=: 1 BAR
1</lang>
JavaScript
<lang javascript>var varname = 'foo'; // pretend a user input that var value = 42; eval('var ' + varname + '=' + value);</lang> Alternatively, without using eval: <lang javascript>var varname = prompt('Variable name:'); var value = 42; this[varname] = value;</lang>
Lasso
Thread vars in Lasso 9 can have dynamic names, but local variables cannot.
The example below outputs a random decimal that was assigned to the variable name entered as part of the GET params. <lang Lasso>local(thename = web_request->param('thename')->asString) if(#thename->size) => {^ var(#thename = math_random) var(#thename) else '<a href="?thename=xyz">Please give the variable a name!</a>' ^}</lang>
Lingo
<lang lingo>-- varName might contain a string that was entered by a user at runtime
-- A new global variable with a user-defined name can be created at runtime like this: (the globals)[varName] = 23 -- or (the globals).setProp(varName, 23)
-- An new instance variable (object property) with a user-defined name can be created at runtime like this: obj[varName] = 23 -- or obj.setProp(varName, 23)</lang>
Logtalk
Logtalk objects can be create or compiled such that new predicates can be added at runtime. A simple example: <lang logtalk> | ?- create_object(Id, [], [set_logtalk_flag(dynamic_declarations,allow)], []),
write('Variable name: '), read(Name), write('Variable value: '), read(Value), Fact =.. [Name, Value], Id::assertz(Fact).
Variable name: foo. Variable value: 42. Id = o1, Name = foo, Value = 42, Fact = foo(42).
?- o1::current_predicate(foo/1). true.
| ?- o1::foo(X). X = 42. </lang>
Lua
<lang lua>_G[io.read()] = 5 --puts 5 in a global variable named by the user</lang>
Logo
<lang logo>? make readword readword julie 12 ? show :julie 12</lang>
M4
<lang M4>Enter foo, please. define(`inp',esyscmd(`echoinp')) define(`trim',substr(inp,0,decr(len(inp)))) define(trim,42) foo</lang>
DOS batch file echoinp.bat:
@echo off set /p Input= echo %Input%
Mathematica / Wolfram Language
<lang Mathematica>varname = InputString["Enter a variable name"]; varvalue = InputString["Enter a value"]; ReleaseHold[ Hold[Set["nameholder", "value"]] /. {"nameholder" -> Symbol[varname], "value" -> varvalue}]; Print[varname, " is now set to ", Symbol[varname]]</lang>
- Example output:
-> testvar is now set to 86
Maxima
<lang maxima>/* Use :: for indirect assignment */ block([name: read("name?"), x: read("value?")], name :: x);</lang>
MUMPS
This is done in immediate mode so you can see the variable is created, although you will have to reference it through the indirection operator, "@". <lang mumps>USER>KILL ;Clean up workspace
USER>WRITE ;show all variables and definitions
USER>READ "Enter a variable name: ",A Enter a variable name: GIBBERISH USER>SET @A=3.14159
USER>WRITE
A="GIBBERISH" GIBBERISH=3.14159</lang>
Octave
<lang octave>varname = input ("Enter variable name: ", "s"); value = input ("Enter value: ", "s"); eval([varname,"=",value]);</lang>
Oforth
<lang oforth>: createVar(varname)
"tvar: " varname + eval ;
"myvar" createVar
12 myvar put myvar at .</lang>
PARI/GP
<lang parigp>eval(Str(input(), "=34"))</lang>
Perl
<lang perl>print "Enter a variable name: "; $varname = <STDIN>; # type in "foo" on standard input chomp($varname); $$varname = 42; # when you try to dereference a string, it will be
# treated as a "symbolic reference", where they # take the string as the name of the variable
print "$foo\n"; # prints "42"</lang> If you are operating in a strict environment, this isn't possible. You need to use 'eval' in this case <lang perl>use strict;
print "Enter a variable name: "; my $foo; my $varname = <STDIN>; # type in "foo" on standard input chomp($varname); my $varref = eval('\$' . $varname); $$varref = 42; print "$foo\n"; # prints "42"</lang>
Perl 6
It is not possible to change lexical variable names at run time, but package variables are fair game, include in the GLOBAL package: <lang perl6>my $vname = prompt 'Variable name: '; $GLOBAL::($vname) = 42; say $GLOBAL::($vname);</lang>
PHP
<lang php><?php $varname = rtrim(fgets(STDIN)); # type in "foo" on standard input $$varname = 42; echo "$foo\n"; # prints "42" ?></lang>
PicoLisp
<lang PicoLisp>(de userVariable ()
(prin "Enter a variable name: ") (let Var (line T) # Read transient symbol (prin "Enter a value: ") (set Var (read)) # Set symbol's value (println 'Variable Var 'Value (val Var)) ) ) # Print them</lang>
- Output:
Enter a variable name: Tom Enter a value: 42 Variable "Tom" Value 42 -> 42
PowerShell
<lang powershell>$variableName = Read-Host New-Variable $variableName 'Foo' Get-Variable $variableName</lang>
ProDOS
<lang>editvar /newvar /value=a /userinput=1 /title=Enter a variable name: editvar /newvar /value=b /userinput=1 /title=Enter a variable title: editvar /newvar /value=-a- /title=-b-</lang>
Python
<lang python>>>> name = raw_input("Enter a variable name: ") Enter a variable name: X >>> globals()[name] = 42 >>> X 42</lang>
<lang python>>>> name = input("Enter a variable name: ") Enter a variable name: X >>> globals()[name] = 42 >>> X 42</lang> Note: most of the time when people ask how to do this on newsgroups and other forums, on investigation, it is found that a neater solution is to map name to value in a dictionary.
R
<lang R># Read the name in from a command prompt varname <- readline("Please name your variable >")
- Make sure the name is valid for a variable
varname <- make.names(varname) message(paste("The variable being assigned is '", varname, "'"))
- Assign the variable (with value 42) into the user workspace (global environment)
assign(varname, 42)
- Check that the value has been assigned ok
ls(pattern=varname) get(varname)</lang>
Racket
This works on the Racket REPL:
<lang Racket> -> (begin (printf "Enter some name: ")
(namespace-set-variable-value! (read) 123))
Enter some name: bleh -> bleh 123 </lang>
REBOL
<lang REBOL>REBOL [ Title: "Dynamic Variable Name" Author: oofoe Date: 2009-12-28 URL: http://rosettacode.org/wiki/Dynamic_variable_names ]
- Here, I ask the user for a name, then convert it to a word and
- assign the value "Hello!" to it. To read this phrase, realize that
- REBOL collects terms from right to left, so "Hello!" is stored for
- future use, then the prompt string "Variable name? " is used as the
- argument to ask (prompts user for input). The result of ask is
- converted to a word so it can be an identifier, then the 'set' word
- accepts the new word and the string ("Hello!") to be assigned.
set to-word ask "Variable name? " "Hello!"</lang>
- Session output:
Variable name? glister == "Hello!" >> glister == "Hello!"
Retro
<lang Retro>: newVariable: ( "- )
getToken header 0 , ;
newVariable: foo</lang> Or: <lang Retro>: newVariable: ( "- )
create 0 , ;
newVariable: foo</lang>
REXX
Checks could've been made to:
- check for the minimum number of arguments
- check for a legitimate REXX variable name
<lang rexx>/*REXX program demonstrates the use of dynamic variable names & setting a val.*/ parse arg newVar newValue say 'Arguments as they were entered via the command line: ' newVar newValue say call value newVar, newValue say 'The newly assigned value (as per the VALUE bif)------' newVar value(newVar)
/*stick a fork in it, we're all done. */</lang>
output for the input: abc 456
Arguments as they were entered via the command line = abc 45678.1 The newly assigned value (as per the VALUE bif)------ abc 45678.1
RLaB
In RLaB all the objects are located in a global list $$. To create a variable dynamically, one writes a new entry into the global list. Consider the following example: <lang RLaB>>> s = "myusername" myusername >> $$.[s] = 10; >> myusername
10</lang>
Ring
<lang ring> See "Enter the variable name: " give cName eval(cName+"=10") See "The variable name = " + cName + " and the variable value = " + eval("return "+cName) + nl </lang> Output <lang ring> Enter the variable name: test The variable name = test and the variable value = 10 </lang>
Ruby
<lang ruby>p "Enter a variable name" x = "@" + gets.chomp! instance_variable_set x, 42 p "The value of #{x} is #{instance_variable_get x}" </lang>
- Example output:
"Enter a variable name" hello "The value of @hello is 42"
Scheme
<lang scheme>=> (define (create-variable name initial-val)
(eval `(define ,name ,initial-val) (interaction-environment)))
=> (create-variable (read) 50) <hello
=> hello 50</lang>
Sidef
It is not possible to create a new lexical variable at run-time, but there are other various ways to do something similar.
<lang ruby>var name = read("Enter a variable name: ", String); # type in 'foo'
class DynamicVar(name, value) {
method init { DynamicVar.def_method(name, ->(_) { value }) }
}
var v = DynamicVar(name, 42); # creates a dynamic variable say v.foo; # retrieves the value</lang>
Slate
Slate symbols are objects that name methods and slots. "Variable definition" is like defining a method which holds the value of a slot, and "variable access" is just method-call to get that value back. <lang slate>define: #name -> (query: 'Enter a variable name: ') intern. "X" define: name -> 42. X print.</lang>
Smalltalk
Define a block-temporary variable with name specified by user input. Set that variable to 42. Print that variable's name and value. <lang smalltalk>| varName | varName := FillInTheBlankMorph request: 'Enter a variable name'. Compiler evaluate: '| ', varName, ' | ', varName, ' := 42. Transcript show: value of ', varName, '; show: is ; show: ', varName.</lang>
SNOBOL4
Indirect string reference of variables is a basic feature of Snobol, using the $ operator. trim( ) is needed for Snobol4+. <lang SNOBOL4>* # Get var name from user
output = 'Enter variable name:' invar = trim(input)
- # Get value from user, assign
output = 'Enter value:' $invar = trim(input)
- Display
output = invar ' == ' $invar
end</lang>
- Output:
Enter variable name: pi Enter value: 3.14159 pi == 3.14159
Tcl
<lang Tcl>puts "Enter a variable name:" gets stdin varname set $varname 42 puts "I have set variable $varname to [set $varname]"</lang> Note that it is more normal to use the user's name to index into a Tcl associative array, as the syntax gets easier to work with in that case: <lang tcl>puts -nonewline "Enter an element name: "; flush stdout gets stdin elemname set ary($elemname) [expr int(rand()*100)] puts "I have set element $elemname to $ary($elemname)"</lang> Another common method for working with dynamic variables is to make an alias to the variable with a fixed name: <lang tcl>puts -nonewline "Enter a variable name: "; flush stdout gets stdin varname upvar 0 $varname v; # The ‘0’ for “current scope” set v [expr int(rand()*100)] puts "I have set variable $varname to $v (see for yourself: [set $varname])"</lang>
TI-89 BASIC
<lang ti89b>Local varName,value InputStr "Variable name", varName Prompt value value → #varName</lang>
TUSCRIPT
<lang tuscript> $$ MODE TUSCRIPT ASK "Enter variablename": name="" ASK "Enter value": value="" TRACE +@name @name=$value PRINT @name </lang> Output:
Enter variablename >test Enter value >Hello World! TRACING Scratch-Datei -*TUSTEP.EDT 5 00 TRACE +@name test = Hello World! Hello World!
zkl
zkl doesn't support adding vars to an existing class but can create a new class with new vars: <lang zkl>vname:="foo"; // or vname:=ask("var name = "); klass:=Compiler.Compiler.compileText("var %s=123".fmt(vname))(); // compile & run the constructor klass.vars.println(); klass.foo.println(); klass.setVar(vname).println(); // setVar(name,val) sets the var</lang>
- Output:
L(L("foo",123)) 123 123
Zsh
<lang zsh>read name typeset $name=42</lang>
- Programming Tasks
- Programming environment operations
- Lily/Omit
- AutoHotkey
- BASIC
- Batch File
- BBC BASIC
- Bracmat
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