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std.array

Functions and types that manipulate built-in arrays and associative arrays.
This module provides all kinds of functions to create, manipulate or convert arrays:

array Returns a copy of the input in a newly allocated dynamic array.
appender Returns a new Appender initialized with a given array.
assocArray Returns a newly allocated associative array from a range of key/value tuples.
byPair Construct a range iterating over an associative array by key/value tuples.
insertInPlace Inserts into an existing array at a given position.
join Concatenates a range of ranges into one array.
minimallyInitializedArray Returns a new array of type T.
replace Returns a new array with all occurrences of a certain subrange replaced.
replaceFirst Returns a new array with the first occurrence of a certain subrange replaced.
replaceInPlace Replaces all occurrences of a certain subrange and puts the result into a given array.
replaceInto Replaces all occurrences of a certain subrange and puts the result into an output range.
replaceLast Returns a new array with the last occurrence of a certain subrange replaced.
replaceSlice Returns a new array with a given slice replaced.
replicate Creates a new array out of several copies of an input array or range.
split Eagerly split a range or string into an array.
uninitializedArray Returns a new array of type T without initializing its elements.
License:
Authors:
Andrei Alexandrescu and Jonathan M Davis

Source: std/array.d

ForeachType!Range[] array(Range)(Range r) if (isIterable!Range && !isNarrowString!Range && !isInfinite!Range);
Allocates an array and initializes it with copies of the elements of range r.
Narrow strings are handled as a special case in an overload.
Parameters:
Range r range (or aggregate with opApply function) whose elements are copied into the allocated array
Returns:
allocated and initialized array
Examples:
auto a = array([1, 2, 3, 4, 5][]);
assert(a == [ 1, 2, 3, 4, 5 ]);
ElementType!String[] array(String)(String str) if (isNarrowString!String);
Convert a narrow string to an array type that fully supports random access. This is handled as a special case and always returns a dchar[], const(dchar)[], or immutable(dchar)[] depending on the constness of the input.
auto assocArray(Range)(Range r) if (isInputRange!Range);
Returns a newly allocated associative array from a range of key/value tuples.
Parameters:
Range r An input range of tuples of keys and values.
Returns:
A newly allocated associative array out of elements of the input range, which must be a range of tuples (Key, Value).
Examples:
import std.range;
import std.typecons;
auto a = assocArray(zip([0, 1, 2], ["a", "b", "c"]));
assert(is(typeof(a) == string[int]));
assert(a == [0:"a", 1:"b", 2:"c"]);

auto b = assocArray([ tuple("foo", "bar"), tuple("baz", "quux") ]);
assert(is(typeof(b) == string[string]));
assert(b == ["foo":"bar", "baz":"quux"]);
auto byPair(Key, Value)(Value[Key] aa);
Construct a range iterating over an associative array by key/value tuples.
Parameters:
Value[Key] aa The associative array to iterate over.
Returns:
A forward range of Tuple's of key and value pairs from the given associative array.
Examples:
import std.typecons : tuple, Tuple;
import std.algorithm : sort;

auto aa = ["a": 1, "b": 2, "c": 3];
Tuple!(string, int)[] pairs;

// Iteration over key/value pairs.
foreach (pair; aa.byPair)
{
    pairs ~= pair;
}

// Iteration order is implementation-dependent, so we should sort it to get
// a fixed order.
sort(pairs);
assert(pairs == [
    tuple("a", 1),
    tuple("b", 2),
    tuple("c", 3)
]);
nothrow @system auto uninitializedArray(T, I...)(I sizes) if (isDynamicArray!T && allSatisfy!(isIntegral, I) && hasIndirections!(ElementEncodingType!T));
Returns a new array of type T allocated on the garbage collected heap without initializing its elements. This can be a useful optimization if every element will be immediately initialized. T may be a multidimensional array. In this case sizes may be specified for any number of dimensions from 0 to the number in T.
uninitializedArray is nothrow and weakly pure.

uninitializedArray is @system if the uninitialized element type has pointers.
nothrow @trusted auto uninitializedArray(T, I...)(I sizes) if (isDynamicArray!T && allSatisfy!(isIntegral, I) && !hasIndirections!(ElementEncodingType!T));
Examples:
double[] arr = uninitializedArray!(double[])(100);
assert(arr.length == 100);

double[][] matrix = uninitializedArray!(double[][])(42, 31);
assert(matrix.length == 42);
assert(matrix[0].length == 31);

char*[] ptrs = uninitializedArray!(char*[])(100);
assert(ptrs.length == 100);
nothrow @trusted auto minimallyInitializedArray(T, I...)(I sizes) if (isDynamicArray!T && allSatisfy!(isIntegral, I));
Returns a new array of type T allocated on the garbage collected heap.
Partial initialization is done for types with indirections, for preservation of memory safety. Note that elements will only be initialized to 0, but not necessarily the element type's .init.

minimallyInitializedArray is nothrow and weakly pure.
void insertInPlace(T, U...)(ref T[] array, size_t pos, U stuff) if (!isSomeString!(T[]) && allSatisfy!(isInputRangeOrConvertible!T, U) && U.length > 0);
void insertInPlace(T, U...)(ref T[] array, size_t pos, U stuff) if (isSomeString!(T[]) && allSatisfy!(isCharOrStringOrDcharRange, U));
Inserts stuff (which must be an input range or any number of implicitly convertible items) in array at position pos.
Examples:
int[] a = [ 1, 2, 3, 4 ];
a.insertInPlace(2, [ 1, 2 ]);
assert(a == [ 1, 2, 1, 2, 3, 4 ]);
a.insertInPlace(3, 10u, 11);
assert(a == [ 1, 2, 1, 10, 11, 2, 3, 4]);
pure nothrow @safe bool sameHead(T)(in T[] lhs, in T[] rhs);
Returns whether the fronts of lhs and rhs both refer to the same place in memory, making one of the arrays a slice of the other which starts at index 0.
pure nothrow @trusted bool sameTail(T)(in T[] lhs, in T[] rhs);
Returns whether the backs of lhs and rhs both refer to the same place in memory, making one of the arrays a slice of the other which end at index $.
ElementEncodingType!S[] replicate(S)(S s, size_t n) if (isDynamicArray!S);
ElementType!S[] replicate(S)(S s, size_t n) if (isInputRange!S && !isDynamicArray!S);
Returns an array that consists of s (which must be an input range) repeated n times. This function allocates, fills, and returns a new array. For a lazy version, refer to std.range.repeat.
pure @safe S[] split(S)(S s) if (isSomeString!S);
Eagerly split the string s into an array of words, using whitespace as delimiter. Runs of whitespace are merged together (no empty words are produced).
@safe, pure and CTFE-able.
See Also:
std.algorithm.splitter for a version that splits using any separator.

std.regex.splitter for a version that splits using a regular expression defined separator.
deprecated alias splitter = std.algorithm.iteration.splitter(alias pred = "a == b", Range, Separator)(Range r, Separator s) if (is(typeof(binaryFun!pred(r.front, s)) : bool) && (hasSlicing!Range && hasLength!Range || isNarrowString!Range));
auto split(Range, Separator)(Range range, Separator sep) if (isForwardRange!Range && is(typeof(ElementType!Range.init == Separator.init)));
auto split(Range, Separator)(Range range, Separator sep) if (isForwardRange!Range && isForwardRange!Separator && is(typeof(ElementType!Range.init == ElementType!Separator.init)));
auto split(alias isTerminator, Range)(Range range) if (isForwardRange!Range && is(typeof(unaryFun!isTerminator(range.front))));
Eagerly splits range into an array, using sep as the delimiter.
The range must be a forward range. The separator can be a value of the same type as the elements in range or it can be another forward range.
Examples:
If range is a string, sep can be a char or another string. The return type will be an array of strings. If range is an int array, sep can be an int or another int array. The return type will be an array of int arrays.
Parameters:
Range range a forward range.
Separator sep a value of the same type as the elements of range or another forward range.
Returns:
An array containing the divided parts of range.
See Also:
std.algorithm.splitter for the lazy version of this function.
ElementEncodingType!(ElementType!RoR)[] join(RoR, R)(RoR ror, R sep) if (isInputRange!RoR && isInputRange!(Unqual!(ElementType!RoR)) && isInputRange!R && is(Unqual!(ElementType!(ElementType!RoR)) == Unqual!(ElementType!R)));
ElementEncodingType!(ElementType!RoR)[] join(RoR, E)(RoR ror, E sep) if (isInputRange!RoR && isInputRange!(Unqual!(ElementType!RoR)) && is(E : ElementType!(ElementType!RoR)));
ElementEncodingType!(ElementType!RoR)[] join(RoR)(RoR ror) if (isInputRange!RoR && isInputRange!(Unqual!(ElementType!RoR)));
Concatenates all of the ranges in ror together into one array using sep as the separator if present.
Parameters:
RoR ror Range of Ranges of Elements
R sep Range of Elements
Returns:
an allocated array of Elements
Examples:
assert(join(["hello", "silly", "world"], " ") == "hello silly world");
assert(join(["hello", "silly", "world"]) == "hellosillyworld");

assert(join([[1, 2, 3], [4, 5]], [72, 73]) == [1, 2, 3, 72, 73, 4, 5]);
assert(join([[1, 2, 3], [4, 5]]) == [1, 2, 3, 4, 5]);

const string[] arr = ["apple", "banana"];
assert(arr.join(",") == "apple,banana");
assert(arr.join() == "applebanana");
E[] replace(E, R1, R2)(E[] subject, R1 from, R2 to) if (isDynamicArray!(E[]) && isForwardRange!R1 && isForwardRange!R2 && (hasLength!R2 || isSomeString!R2));
Replace occurrences of from with to in subject. Returns a new array without changing the contents of subject, or the original array if no match is found.
Examples:
assert("Hello Wörld".replace("o Wö", "o Wo") == "Hello World");
assert("Hello Wörld".replace("l", "h") == "Hehho Wörhd");
void replaceInto(E, Sink, R1, R2)(Sink sink, E[] subject, R1 from, R2 to) if (isOutputRange!(Sink, E) && isDynamicArray!(E[]) && isForwardRange!R1 && isForwardRange!R2 && (hasLength!R2 || isSomeString!R2));
Same as above, but outputs the result via OutputRange sink. If no match is found the original array is transferred to sink as is.
T[] replace(T, Range)(T[] subject, size_t from, size_t to, Range stuff) if (isInputRange!Range && (is(ElementType!Range : T) || isSomeString!(T[]) && is(ElementType!Range : dchar)));
Replaces elements from array with indices ranging from from (inclusive) to to (exclusive) with the range stuff. Returns a new array without changing the contents of subject.
Examples:
auto a = [ 1, 2, 3, 4 ];
auto b = a.replace(1, 3, [ 9, 9, 9 ]);
assert(a == [ 1, 2, 3, 4 ]);
assert(b == [ 1, 9, 9, 9, 4 ]);
void replaceInPlace(T, Range)(ref T[] array, size_t from, size_t to, Range stuff) if (isDynamicArray!Range && is(ElementEncodingType!Range : T) && !is(T == const(T)) && !is(T == immutable(T)));
void replaceInPlace(T, Range)(ref T[] array, size_t from, size_t to, Range stuff) if (isInputRange!Range && (!isDynamicArray!Range && is(ElementType!Range : T) || isDynamicArray!Range && is(ElementType!Range : T) && (is(T == const(T)) || is(T == immutable(T))) || isSomeString!(T[]) && is(ElementType!Range : dchar)));
Replaces elements from array with indices ranging from from (inclusive) to to (exclusive) with the range stuff. Expands or shrinks the array as needed.
Examples:
int[] a = [1, 4, 5];
replaceInPlace(a, 1u, 2u, [2, 3, 4]);
assert(a == [1, 2, 3, 4, 5]);
replaceInPlace(a, 1u, 2u, cast(int[])[]);
assert(a == [1, 3, 4, 5]);
replaceInPlace(a, 1u, 3u, a[2 .. 4]);
assert(a == [1, 4, 5, 5]);
E[] replaceFirst(E, R1, R2)(E[] subject, R1 from, R2 to) if (isDynamicArray!(E[]) && isForwardRange!R1 && is(typeof(appender!(E[])().put(from[0..1]))) && isForwardRange!R2 && is(typeof(appender!(E[])().put(to[0..1]))));
Replaces the first occurrence of from with to in a. Returns a new array without changing the contents of subject, or the original array if no match is found.
Examples:
auto a = [1, 2, 2, 3, 4, 5];
auto b = a.replaceFirst([2], [1337]);
assert(b == [1, 1337, 2, 3, 4, 5]);

auto s = "This is a foo foo list";
auto r = s.replaceFirst("foo", "silly");
assert(r == "This is a silly foo list");
E[] replaceLast(E, R1, R2)(E[] subject, R1 from, R2 to) if (isDynamicArray!(E[]) && isForwardRange!R1 && is(typeof(appender!(E[])().put(from[0..1]))) && isForwardRange!R2 && is(typeof(appender!(E[])().put(to[0..1]))));
Replaces the last occurrence of from with to in a. Returns a new array without changing the contents of subject, or the original array if no match is found.
Examples:
auto a = [1, 2, 2, 3, 4, 5];
auto b = a.replaceLast([2], [1337]);
assert(b == [1, 2, 1337, 3, 4, 5]);

auto s = "This is a foo foo list";
auto r = s.replaceLast("foo", "silly");
assert(r == "This is a foo silly list", r);
inout(T)[] replaceSlice(T)(inout(T)[] s, in T[] slice, in T[] replacement);
Returns a new array that is s with slice replaced by replacement[].
struct Appender(A) if (isDynamicArray!A);
Implements an output range that appends data to an array. This is recommended over a ~= data when appending many elements because it is more efficient.
Examples:
auto app = appender!string();
string b = "abcdefg";
foreach (char c; b)
    app.put(c);
assert(app.data == "abcdefg");

int[] a = [ 1, 2 ];
auto app2 = appender(a);
app2.put(3);
app2.put([ 4, 5, 6 ]);
assert(app2.data == [ 1, 2, 3, 4, 5, 6 ]);
pure nothrow @trusted this(T[] arr);
Construct an appender with a given array. Note that this does not copy the data. If the array has a larger capacity as determined by arr.capacity, it will be used by the appender. After initializing an appender on an array, appending to the original array will reallocate.
pure nothrow @safe void reserve(size_t newCapacity);
Reserve at least newCapacity elements for appending. Note that more elements may be reserved than requested. If newCapacity <= capacity, then nothing is done.
const pure nothrow @property @safe size_t capacity();
Returns the capacity of the array (the maximum number of elements the managed array can accommodate before triggering a reallocation). If any appending will reallocate, capacity returns 0.
inout pure nothrow @property @trusted inout(T)[] data();
Returns the managed array.
void put(U)(U item) if (canPutItem!U);
Appends one item to the managed array.
void put(Range)(Range items) if (canPutRange!Range);
Appends an entire range to the managed array.
void opOpAssign(string op : "~", U)(U item) if (canPutItem!U);
Appends one item to the managed array.
void opOpAssign(string op : "~", Range)(Range items) if (canPutRange!Range);
Appends an entire range to the managed array.
pure nothrow @trusted void clear();
Clears the managed array. This allows the elements of the array to be reused for appending.
Note that clear is disabled for immutable or const element types, due to the possibility that Appender might overwrite immutable data.
pure @trusted void shrinkTo(size_t newlength);
Shrinks the managed array to the given length.
Throws:
Exception if newlength is greater than the current array length.
struct RefAppender(A) if (isDynamicArray!A);
An appender that can update an array in-place. It forwards all calls to an underlying appender implementation. Any calls made to the appender also update the pointer to the original array passed in.
this(T[]* arr);
Construct a ref appender with a given array reference. This does not copy the data. If the array has a larger capacity as determined by arr.capacity, it will be used by the appender. RefAppender assumes that arr is a non-null value.
Note, do not use builtin appending (i.e. ~=) on the original array passed in until you are done with the appender, because calls to the appender override those appends.
void opOpAssign(string op : "~", U)(U item) if (AppenderType.canPutItem!U);
Appends one item to the managed array.
void opOpAssign(string op : "~", Range)(Range items) if (AppenderType.canPutRange!Range);
Appends an entire range to the managed array.
const @property size_t capacity();
Returns the capacity of the array (the maximum number of elements the managed array can accommodate before triggering a reallocation). If any appending will reallocate, capacity returns 0.
inout @property inout(T)[] data();
Returns the managed array.
Appender!A appender(A)() if (isDynamicArray!A);
Appender!(E[]) appender(A : E[], E)(auto ref A array);
Convenience function that returns an Appender!A object initialized with array.
RefAppender!(E[]) appender(A : E[]*, E)(A array);
Convenience function that returns a RefAppender!A object initialized with array. Don't use null for the array pointer, use the other version of appender instead.