/* Module "array.wren" */
import "meta" for Meta
import "./check" for Check
/*
Array represents a List whose size cannot be changed after it has been constructed
but whose elements can be changed. If an array is created from a list, the
list is shallow-copied, not cloned.
*/
class Array is Sequence {
// Constructs a new array from a List or other Sequence.
construct from(a) {
Check.seq("Argument", a)
_a = a.toList // create a list or shallow copy if the argument is already a list.
}
// Constructs a new array from a List or other Sequence by fitting it to a given size
// truncating if it's too big or filling out with a given value if it's too small.
construct fit(size, a, v) {
Check.nonNegInt("Size", size)
Check.seq("Second argument", a)
a = a.toList
if (a.count == size) {
_a = a
} else if (a.count > size) {
_a = a[0...size]
} else {
_a = a
for (i in a.count...size) _a.add(v)
}
}
// Convenience version of 'fit' which uses a default value of null.
static fit(size, a) { fit(size, a, null) }
// Constructs a new array of a given size and sets all elements to the same value 'v'.
construct new(size, v) {
Check.nonNegInt("Size", size)
_a = List.filled(size, v)
}
// Convenience version of 'new' which sets all elements to null.
static new(size) { new(size, null) }
// Property
count { _a.count } // returns the number of elements in the array
// Creates a shallow copy of the current instance.
copy() { Array.from(_a) }
// Resets all elements of the array to 'v'.
reset(v) {
for (i in 0..._a.count) _a[i] = v
}
// Gets the element at 'index.' If index is negative, it counts backwards
// from the end of the array where -1 is the last element.
// If index is a range it creates a new array from the appropriate elements.
[index] { (index is Range) ? Array.from(_a[index]) : _a[index] }
// Sets the element at 'index'. Negative indices are treated as in the getter.
[index]=(v) { _a[index] = v }
// Returns the index of 'value' in the current instance or -1 if 'value' is not found.
indexOf(value) { _a.indexOf(value) }
// Returns the index of the last occurrence of 'value' in the current instance
// or -1 if 'value' is not found.
lastIndexOf(value) {
if (_a.count == 0) return 0
for (i in _a.count-1..0) {
if (_a[i] == value) return i
}
return -1
}
// Replaces all occurrences of 'old' by 'new' in the current instance
// and returns ['old', 'new'].
replace(old, new) {
for (i in 0..._a.count) {
if (_a[i] == old) _a[i] = new
}
return [old, new]
}
// Sorts the elements of the array in place and both overloads work in exactly
// the same manner as the corresponding methods in the List class.
sort() { _a.sort() }
sort(comparer) { _a.sort(comparer) }
// Swaps the elements at index1 and index2 within the array.
swap(index1, index2) { _a.swap(index1, index2) }
// Applies a function to each element of the array.
apply(fn) {
Check.func("fn", fn, 1)
for (i in 0..._a.count) _a[i] = fn.call(_a[i])
}
// Iterator protocol methods.
iterate(iterator) { _a.iterate(iterator) }
iteratorValue(iterator) { _a.iteratorValue(iterator) }
// Returns the string representation of the underlying list.
toString { _a.toString }
}
/*
ArrayType creates a named class which inherits from Array and always has the same
size and default values. The named class has four constructors:
1. new(v) - sets all elements to 'v'
2. new() - sets all elements to the default value
3. fit(a, v) - fits the sequence 'a' to 'size' filling out with 'v' if too short
4. fit(a) - as (3) but fills out with the default value if too short
and four instance methods of its own:
5. default - returns the default value
6. toArray - converts the current instance to an Array
7. copy() - creates a shallow copy of the current instance
- overriding the copy() method inherited from Array
8. reset() - resets all elements to the default value.
*/
class ArrayType {
// Creates a class for the ArrayType (with an underscore after the name), with a
// given size and default value for its elements, and returns a reference to it.
static create(name, size, default) {
Check.ident("Name", name)
Check.nonNegInt("Size", size)
name = name + "_"
var s = "class %(name) is Array {\n"
s = s + " construct new(v) {\n"
s = s + " super(%(size), v)\n"
s = s + " }\n"
s = s + " construct new() {\n"
s = s + " super(%(size), %(default))\n"
s = s + " }\n"
s = s + " construct fit(a, v) {\n"
s = s + " super(%(size), a, v)\n"
s = s + " }\n"
s = s + " construct fit(a) {\n"
s = s + " super(%(size), a, %(default))\n"
s = s + " }\n"
s = s + " default { %(default) }\n"
s = s + " toArray() { Array.from(this) }\n"
s = s + " copy() {\n"
s = s + " var d = %(name).new()\n"
s = s + " for (i in 0...%(size)) d[i] = this[i]\n"
s = s + " return d\n"
s = s + " }\n"
s = s + " reset() { reset(%(default)) }\n}\n"
s = s + "return %(name)"
return Meta.compile(s).call()
}
// Convenience version of 'create' which always uses a default value of null.
static create(name, size ) { create(name, size, null) }
}
/*
BitArray represents a List<Bool> whose size cannot be changed after it has been constructed
but whose elements can be changed. It uses only 1/32nd as much memory as a 'normal' List<Bool>
but is around 4 times slower to index. Also, unlike List<Bool>, BitArray is not a Sequence.
*/
class BitArray {
// Constructs a new BitArray of a given size and sets all elements to the same value 'v'.
// 'size' is rounded to the higher multiple of 32 where necessary.
construct new(size, v) {
Check.posInt("size", size)
Check.bool("value", v)
_len = (size / 32).ceil
_a = List.filled(_len, v ? 4294967295 : 0)
}
// Convenience version of 'new' which sets all elements to false.
static new(size) { new(size, false) }
// Returns the number of elements in the BitArray.
count { 32 * _len }
// Creates a copy of the current instance.
copy() {
var c = BitArray.new(count, false)
for (i in 0...count) c[i] = this[i]
return c
}
// Resets all elements of the BitArray to 'v'.
reset(v) {
Check.bool("value", v)
var value = v ? 4294967295 : 0
for (i in 0..._len) _a[i] = value
}
// Gets the element at 'index'. If index is negative, it counts backwards
// from the end of the array where -1 is the last element.
// To maximize access speed, this method doesn't validate the index.
// Use the 'get' method instead if you need to do that.
[index] {
if (index < 0) index = count + index
var ix = (index/32).floor
var bit = index%32
return ((_a[ix] >> bit) & 1) == 1
}
// Sets the element at 'index'. Negative indices are treated as in the getter.
// To maximize access speed, this method doesn't validate the index nor the new value.
// Use the 'set' method instead if you need to do that.
[index]=(v) {
if (index < 0) index = count + index
var ix = (index/32).floor
var bit = index%32
_a[ix] = v ? _a[ix] | (1 << bit) : _a[ix] & ~(1 << bit)
}
// As [index] method but validates the index.
get(index) {
Check.int("index", index, -count, count-1)
return this[index]
}
// As [index]=(v) method but validates the index and the new value.
set(index, v) {
Check.int("index", index, -count, count-1)
Check.bool("value", v)
this[index] = v
}
// Returns a List<Bool> using the normal 8 bytes for each element.
toList {
var bools = List.filled(count, false)
for (i in 0...count) bools[i] = this[i]
return bools
}
// Returns an Array<Bool> using the normal 8 bytes for each element.
toArray {
var bools = Array.new(count, false)
for (i in 0...count) bools[i] = this[i]
return bools
}
// Returns a bit string representation of this BitArray.
toString {
var bytes = List.filled(count, 0)
for (i in 0...count) if (this[i]) bytes[i] = 1
return bytes.join()
}
}
/*
ByteArray represents a List<Byte> whose size cannot be changed after it has been constructed
but whose elements can be changed. A 'Byte' for this purpose is an integral Num with a value
between 0 and 255 inclusive. It uses only a quarter as much memory as a 'normal' List<Byte>
but is around 4 times slower to index. Also, unlike List<Byte>, ByteArray is not a Sequence.
*/
class ByteArray {
// Constructs a new ByteArray of a given size and sets all elements to the same value 'v'.
// 'size' is rounded to the higher multiple of 4 where necessary.
construct new(size, v) {
Check.posInt("size", size)
Check.int("value", v, 0, 255)
_len = (size / 4).ceil
// convert 'v' to a little-endian 32-bit unsigned integer.
v = (v == 0) ? 0 : v | v << 8 | v << 16 | v << 24
_a = List.filled(_len, v)
}
// Constructs a new ByteArray from a List<Byte>, optionally checking that the byte
// values are valid. Where necessary, the size of the ByteArray is rounded to the
// higher multiple of 4 and filled out with zero values.
construct fromList(a, checkBytes) {
Check.typedList("a", a, "Int", 1)
Check.bool("checkBytes", checkBytes)
_len = (a.count / 4).ceil
_a = List.filled(_len, 0)
if (checkBytes) {
for (i in 0...a.count) {
if (!(a[i].isInteger && a[i] >= 0 && a[i] < 256)) {
Fiber.abort("a[%(i)] = %(a[i]) is not a byte.")
}
}
}
for (i in 0..._len) {
var j = i * 4
if (i < _len - 1) {
_a[i] = a[j] | a[j+1] << 8 | a[j+2] << 16 | a[j+3] << 24
} else {
var b2 = (j + 1 < a.count) ? a[j+1] : 0
var b3 = (j + 2 < a.count) ? a[j+2] : 0
var b4 = (j + 3 < a.count) ? a[j+3] : 0
_a[i] = a[j] | b2 << 8 | b3 << 16 | b4 << 24
}
}
}
// Constructs a new ByteArray from a lower case hexadecimal string.
// Where necessary, the size of the ByteArray is rounded to the
// higher multiple of 4 and filled out with zero values.
static fromHexString(hs) {
Check.str("hs", hs, 2)
if (hs.count % 2 != 0) {
Fiber.abort("'hs' must contain an even number of hex digits >= 2.")
}
var digits = "0123456789abcdef"
var bytes = List.filled(hs.count/2, 0)
var i = 0
while (i < hs.count-1) {
bytes[i/2] = digits.indexOf(hs[i]) * 16 + digits.indexOf(hs[i+1])
i = i + 2
}
return fromList(bytes, false)
}
// As 'fromList' except constructs the new ByteArray from an Array<Byte> instead.
static fromArray(a, checkBytes) { fromList(a.toList, checkBytes) }
// Convenience version of 'new' which sets all elements to zero.
static new(size) { new(size, 0) }
// Convenience version of 'fromList' which does not check that the byte values are valid.
static fromList(a) { fromList(a, false) }
// Convenience version of 'fromArray' which does not check that the byte values are valid.
static fromArray(a) { fromList(a.toList, false) }
// Returns the number of elements in the ByteArray.
count { 4 * _len }
// Creates a copy of the current instance.
copy() {
var c = ByteArray.new(count, 0)
for (i in 0...count) c[i] = this[i]
return c
}
// Resets all elements of the ByteArray to 'v'.
reset(v) {
Check.int("value", v, 0, 255)
v = (v == 0) ? 0 : v | v << 8 | v << 16 | v << 24
for (i in 0..._len) _a[i] = v
}
// Gets the element at 'index'. If index is negative, it counts backwards
// from the end of the array where -1 is the last element.
// To maximize access speed, this method doesn't validate the index.
// Use the 'get' method instead if you need to do that.
[index] {
if (index < 0) index = count + index
var ix = (index/4).floor
var bit = (index%4) * 8
return (_a[ix] >> bit) & 255
}
// Sets the element at 'index'. Negative indices are treated as in the getter.
// To maximize access speed, this method doesn't validate the index nor the new value.
// Use the 'set' method instead if you need to do that.
[index]=(v) {
if (index < 0) index = count + index
var ix = (index/4).floor
var bit = (index%4) * 8
_a[ix] = (_a[ix] & ~(255 << bit)) | (v << bit)
}
// As [index] method but validates the index.
get(index) {
Check.int("index", index, -count, count-1)
return this[index]
}
// As [index]=(v) method but validates the index and the new value.
set(index, v) {
Check.int("index", index, -count, count-1)
Check.int("value", v, 0, 255)
this[index] = v
}
// Returns a List<Byte> using the normal 8 bytes for each element.
toList {
var bytes = List.filled(count, 0)
for (i in 0...count) bytes[i] = this[i]
return bytes
}
// Returns an Array<Byte> using the normal 8 bytes for each element.
toArray {
var bytes = Array.new(count, 0)
for (i in 0...count) bytes[i] = this[i]
return bytes
}
// Returns a string representation of this instance as if it were a list.
toString { toList.toString }
// Returns a lower case hex string representation of this instance.
toHexString {
var digits = "0123456789abcdef"
return toList.reduce("") { |acc, b| acc + digits[b>>4] + digits[b%16] }
}
}
