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std.container.array

This module provides an Array type with deterministic memory usage not reliant on the GC, as an alternative to the built-in arrays.
This module is a submodule of std.container.
License:
Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at boost.org/LICENSE_1_0.txt).
Examples:
auto arr = Array!int(0, 2, 3);
writeln(arr[0]); // 0
writeln(arr.front); // 0
writeln(arr.back); // 3

// reserve space
arr.reserve(1000);
writeln(arr.length); // 3
assert(arr.capacity >= 1000);

// insertion
arr.insertBefore(arr[1..$], 1);
writeln(arr.front); // 0
writeln(arr.length); // 4

arr.insertBack(4);
writeln(arr.back); // 4
writeln(arr.length); // 5

// set elements
arr[1] *= 42;
writeln(arr[1]); // 42
Examples:
import std.algorithm.comparison : equal;
auto arr = Array!int(1, 2, 3);

// concat
auto b = Array!int(11, 12, 13);
arr ~= b;
writeln(arr.length); // 6

// slicing
assert(arr[1..3].equal([2, 3]));

// remove
arr.linearRemove(arr[1..3]);
assert(arr[0..2].equal([1, 11]));
Examples:
Array!bool packs together values efficiently by allocating one bit per element
Array!bool arr;
arr.insert([true, true, false, true, false]);
writeln(arr.length); // 5
struct Array(T) if (!is(Unqual!T == bool));
Array type with deterministic control of memory. The memory allocated for the array is reclaimed as soon as possible; there is no reliance on the garbage collector. Array uses malloc and free for managing its own memory.
This means that pointers to elements of an Array will become dangling as soon as the element is removed from the Array. On the other hand the memory allocated by an Array will be scanned by the GC and GC managed objects referenced from an Array will be kept alive.

Note: When using Array with range-based functions like those in std.algorithm, Array must be sliced to get a range (for example, use array[].map! instead of array.map!). The container itself is not a range.

this(U)(U[] values...)
if (isImplicitlyConvertible!(U, T));
Constructor taking a number of items
this(Stuff)(Stuff stuff)
if (isInputRange!Stuff && isImplicitlyConvertible!(ElementType!Stuff, T) && !is(Stuff == T[]));
Constructor taking an input range
const bool opEquals(const Array rhs);

const bool opEquals(ref const Array rhs);
Comparison for equality.
alias Range = RangeT!Array;

alias ConstRange = RangeT!(const(Array));

alias ImmutableRange = RangeT!(immutable(Array));
Defines the container's primary range, which is a random-access range.
ConstRange is a variant with const elements. ImmutableRange is a variant with immutable elements.
@property Array dup();
Duplicates the container. The elements themselves are not transitively duplicated.

Complexity: Ο(n).

const @property bool empty();
Property returning true if and only if the container has no elements.

Complexity: Ο(1)

const @property size_t length();

const size_t opDollar();
Returns the number of elements in the container.

Complexity: Ο(1).

@property size_t capacity();
Returns the maximum number of elements the container can store without (a) allocating memory, (b) invalidating iterators upon insertion.

Complexity: Ο(1)

void reserve(size_t elements);
Ensures sufficient capacity to accommodate e elements.

Postcondition: capacity >= e

Complexity: Ο(1)

Range opSlice();
Returns a range that iterates over elements of the container, in forward order.

Complexity: Ο(1)

Range opSlice(size_t i, size_t j);
Returns a range that iterates over elements of the container from index a up to (excluding) index b.

Precondition: a <= b && b <= length

Complexity: Ο(1)

inout @property ref inout(T) front();

inout @property ref inout(T) back();
Forward to opSlice().front and opSlice().back, respectively.

Precondition: !empty

Complexity: Ο(1)

inout ref inout(T) opIndex(size_t i);
Indexing operators yield or modify the value at a specified index.

Precondition: i < length

Complexity: Ο(1)

void opSliceAssign(T value);

void opSliceAssign(T value, size_t i, size_t j);

void opSliceUnary(string op)()
if (op == "++" || op == "--");

void opSliceUnary(string op)(size_t i, size_t j)
if (op == "++" || op == "--");

void opSliceOpAssign(string op)(T value);

void opSliceOpAssign(string op)(T value, size_t i, size_t j);
Slicing operations execute an operation on an entire slice.

Precondition: i < j && j < length

Complexity: Ο(slice.length)

Array opBinary(string op, Stuff)(Stuff stuff)
if (op == "~");
Returns a new container that's the concatenation of this and its argument. opBinaryRight is only defined if Stuff does not define opBinary.

Complexity: Ο(n + m), where m is the number of elements in stuff

void opOpAssign(string op, Stuff)(Stuff stuff)
if (op == "~");
Forwards to insertBack(stuff).
void clear();
Removes all contents from the container. The container decides how capacity is affected.

Postcondition: empty

Complexity: Ο(n)

@property void length(size_t newLength);
Sets the number of elements in the container to newSize. If newSize is greater than length, the added elements are added to unspecified positions in the container and initialized with T.init.

Complexity: Ο(abs(n - newLength))

Postcondition: length == newLength

T removeAny();

alias stableRemoveAny = removeAny;
Picks one value in an unspecified position in the container, removes it from the container, and returns it. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.

Precondition: !empty

Returns:
The element removed.

Complexity: Ο(log(n)).

size_t insertBack(Stuff)(Stuff stuff)
if (isImplicitlyConvertible!(Stuff, T) || isInputRange!Stuff && isImplicitlyConvertible!(ElementType!Stuff, T));

alias insert = insertBack;
Inserts value to the front or back of the container. stuff can be a value convertible to T or a range of objects convertible to T. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.
Returns:
The number of elements inserted

Complexity: Ο(m * log(n)), where m is the number of elements in stuff

void removeBack();

alias stableRemoveBack = removeBack;
Removes the value at the back of the container. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.

Precondition: !empty

Complexity: Ο(log(n)).

size_t removeBack(size_t howMany);

alias stableRemoveBack = removeBack;
Removes howMany values at the front or back of the container. Unlike the unparameterized versions above, these functions do not throw if they could not remove howMany elements. Instead, if howMany > n, all elements are removed. The returned value is the effective number of elements removed. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.
Returns:
The number of elements removed

Complexity: Ο(howMany).

size_t insertBefore(Stuff)(Range r, Stuff stuff)
if (isImplicitlyConvertible!(Stuff, T));

size_t insertBefore(Stuff)(Range r, Stuff stuff)
if (isInputRange!Stuff && isImplicitlyConvertible!(ElementType!Stuff, T));

size_t insertAfter(Stuff)(Range r, Stuff stuff);

size_t replace(Stuff)(Range r, Stuff stuff)
if (isInputRange!Stuff && isImplicitlyConvertible!(ElementType!Stuff, T));

size_t replace(Stuff)(Range r, Stuff stuff)
if (isImplicitlyConvertible!(Stuff, T));
Inserts stuff before, after, or instead range r, which must be a valid range previously extracted from this container. stuff can be a value convertible to T or a range of objects convertible to T. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.
Returns:
The number of values inserted.

Complexity: Ο(n + m), where m is the length of stuff

Range linearRemove(Range r);
Removes all elements belonging to r, which must be a range obtained originally from this container. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.
Returns:
A range spanning the remaining elements in the container that initially were right after r.

Complexity: Ο(n - m), where m is the number of elements in r

struct Array(T) if (is(Unqual!T == bool));
Array specialized for bool. Packs together values efficiently by allocating one bit per element.
struct Range;
Defines the container's primary range.
@property Range save();

@property bool empty();

@property T front();

@property void front(bool value);

T moveFront();

void popFront();

@property T back();

@property void back(bool value);

T moveBack();

void popBack();

T opIndex(size_t i);

void opIndexAssign(T value, size_t i);

T moveAt(size_t i);

const @property size_t length();

Range opSlice(size_t low, size_t high);
Range primitives
@property bool empty();
Property returning true if and only if the container has no elements.

Complexity: Ο(1)

@property Array dup();
Returns a duplicate of the container. The elements themselves are not transitively duplicated.

Complexity: Ο(n).

const @property size_t length();
Returns the number of elements in the container.

Complexity: Ο(log(n)).

@property size_t capacity();
Returns the maximum number of elements the container can store without (a) allocating memory, (b) invalidating iterators upon insertion.

Complexity: Ο(log(n)).

void reserve(size_t e);
Ensures sufficient capacity to accommodate n elements.

Postcondition: capacity >= n

Complexity: Ο(log(e - capacity)) if e > capacity, otherwise Ο(1).

Range opSlice();
Returns a range that iterates over all elements of the container, in a container-defined order. The container should choose the most convenient and fast method of iteration for opSlice().

Complexity: Ο(log(n))

Range opSlice(size_t a, size_t b);
Returns a range that iterates the container between two specified positions.

Complexity: Ο(log(n))

@property bool front();

@property void front(bool value);

@property bool back();

@property void back(bool value);
Equivalent to opSlice().front and opSlice().back, respectively.

Complexity: Ο(log(n))

bool opIndex(size_t i);

void opIndexAssign(bool value, size_t i);

void opIndexOpAssign(string op)(bool value, size_t i);

T moveAt(size_t i);
Indexing operators yield or modify the value at a specified index.
Array!bool opBinary(string op, Stuff)(Stuff rhs)
if (op == "~");
Returns a new container that's the concatenation of this and its argument.

Complexity: Ο(n + m), where m is the number of elements in stuff

Array!bool opOpAssign(string op, Stuff)(Stuff stuff)
if (op == "~");
Forwards to insertAfter(this[], stuff).
void clear();
Removes all contents from the container. The container decides how capacity is affected.

Postcondition: empty

Complexity: Ο(n)

@property void length(size_t newLength);
Sets the number of elements in the container to newSize. If newSize is greater than length, the added elements are added to the container and initialized with ElementType.init.

Complexity: Ο(abs(n - newLength))

Postcondition: length == newLength

alias insert = insertBack;

alias stableInsert = insertBack;
Inserts stuff in the container. stuff can be a value convertible to ElementType or a range of objects convertible to ElementType.
The stable version guarantees that ranges iterating over the container are never invalidated. Client code that counts on non-invalidating insertion should use stableInsert.
Returns:
The number of elements added.

Complexity: Ο(m * log(n)), where m is the number of elements in stuff

alias linearInsert = insertBack;

alias stableLinearInsert = insertBack;
Same as insert(stuff) and stableInsert(stuff) respectively, but relax the complexity constraint to linear.
T removeAny();

alias stableRemoveAny = removeAny;
Picks one value in the container, removes it from the container, and returns it. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.

Precondition: !empty

Returns:
The element removed.

Complexity: Ο(log(n))

size_t insertBack(Stuff)(Stuff stuff)
if (is(Stuff : bool));

size_t insertBack(Stuff)(Stuff stuff)
if (isInputRange!Stuff && is(ElementType!Stuff : bool));

alias stableInsertBack = insertBack;
Inserts value to the back of the container. stuff can be a value convertible to ElementType or a range of objects convertible to ElementType. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.
Returns:
The number of elements inserted

Complexity: Ο(log(n))

void removeBack();

alias stableRemoveBack = removeBack;
Removes the value at the front or back of the container. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated. The optional parameter howMany instructs removal of that many elements. If howMany > n, all elements are removed and no exception is thrown.

Precondition: !empty

Complexity: Ο(log(n)).

size_t removeBack(size_t howMany);
Removes howMany values at the front or back of the container. Unlike the unparameterized versions above, these functions do not throw if they could not remove howMany elements. Instead, if howMany > n, all elements are removed. The returned value is the effective number of elements removed. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.
Returns:
The number of elements removed

Complexity: Ο(howMany * log(n)). ditto

size_t insertBefore(Stuff)(Range r, Stuff stuff);

alias stableInsertBefore = insertBefore;

size_t insertAfter(Stuff)(Range r, Stuff stuff);

alias stableInsertAfter = insertAfter;

size_t replace(Stuff)(Range r, Stuff stuff)
if (is(Stuff : bool));

alias stableReplace = replace;
Inserts stuff before, after, or instead range r, which must be a valid range previously extracted from this container. stuff can be a value convertible to ElementType or a range of objects convertible to ElementType. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.
Returns:
The number of values inserted.

Complexity: Ο(n + m), where m is the length of stuff

Range linearRemove(Range r);
Removes all elements belonging to r, which must be a range obtained originally from this container. The stable version behaves the same, but guarantees that ranges iterating over the container are never invalidated.
Returns:
A range spanning the remaining elements in the container that initially were right after r.

Complexity: Ο(n)