The Sequence interface

Introduction

A Sequence describes the behaviour of values arranged in a single, linear dimension. Some languages refer to this as a "List". It’s similar to an array that uses incremental integer keys, with the exception of a few characteristics:

Values will always be indexed as [0, 1, 2, …, size - 1].
Only allowed to access values by index in the range [0, size - 1].

Use cases:

Wherever you would use an array as a list (not concerned with keys).
A more efficient alternative to SplDoublyLinkedList and SplFixedArray.

Interface synopsis

Ds\Sequence extends Ds\Collection ArrayAccess

/* Methods */

abstract public void Ds\Sequence::allocate(int $capacity)

abstract public void Ds\Sequence::apply(callable $callback)

abstract public int Ds\Sequence::capacity()

abstract public bool Ds\Sequence::contains(mixed ...$values)

abstract public Ds\Sequence Ds\Sequence::filter(callable $callback = ?)

abstract public mixed Ds\Sequence::find(mixed $value)

abstract public mixed Ds\Sequence::first()

abstract public mixed Ds\Sequence::get(int $index)

abstract public void Ds\Sequence::insert(int $index, mixed ...$values)

abstract public string Ds\Sequence::join(string $glue = ?)

abstract public mixed Ds\Sequence::last()

abstract public Ds\Sequence Ds\Sequence::map(callable $callback)

abstract public Ds\Sequence Ds\Sequence::merge(mixed $values)

abstract public mixed Ds\Sequence::pop()

abstract public void Ds\Sequence::push(mixed ...$values)

abstract public mixed Ds\Sequence::reduce(callable $callback, mixed $initial = ?)

abstract public mixed Ds\Sequence::remove(int $index)

abstract public void Ds\Sequence::reverse()

abstract public Ds\Sequence Ds\Sequence::reversed()

abstract public void Ds\Sequence::rotate(int $rotations)

abstract public void Ds\Sequence::set(int $index, mixed $value)

abstract public mixed Ds\Sequence::shift()

abstract public Ds\Sequence Ds\Sequence::slice(int $index, int $length = ?)

abstract public void Ds\Sequence::sort(callable $comparator = ?)

abstract public Ds\Sequence Ds\Sequence::sorted(callable $comparator = ?)

abstract public intfloat Ds\Sequence::sum()

abstract public void Ds\Sequence::unshift(mixed $values = ?)

/* Inherited methods */

public void Ds\Collection::clear()

public Ds\Collection Ds\Collection::copy()

public bool Ds\Collection::isEmpty()

public array Ds\Collection::toArray()

public int Countable::count()

public Traversable IteratorAggregate::getIterator()

public mixed JsonSerializable::jsonSerialize()

public bool ArrayAccess::offsetExists(mixed $offset)

public mixed ArrayAccess::offsetGet(mixed $offset)

public void ArrayAccess::offsetSet(mixed $offset, mixed $value)

public void ArrayAccess::offsetUnset(mixed $offset)

Changelog

Version	Description
PECL ds 1.3.0	The interface now extends ArrayAccess.

Table of Contents

Ds\Sequence::allocate — Allocates enough memory for a required capacity
Ds\Sequence::apply — Updates all values by applying a callback function to each value
Ds\Sequence::capacity — Returns the current capacity
Ds\Sequence::contains — Determines if the sequence contains given values
Ds\Sequence::filter — Creates a new sequence using a callable to determine which values to include
Ds\Sequence::find — Attempts to find a value's index
Ds\Sequence::first — Returns the first value in the sequence
Ds\Sequence::get — Returns the value at a given index
Ds\Sequence::insert — Inserts values at a given index
Ds\Sequence::join — Joins all values together as a string
Ds\Sequence::last — Returns the last value
Ds\Sequence::map — Returns the result of applying a callback to each value
Ds\Sequence::merge — Returns the result of adding all given values to the sequence
Ds\Sequence::pop — Removes and returns the last value
Ds\Sequence::push — Adds values to the end of the sequence
Ds\Sequence::reduce — Reduces the sequence to a single value using a callback function
Ds\Sequence::remove — Removes and returns a value by index
Ds\Sequence::reverse — Reverses the sequence in-place
Ds\Sequence::reversed — Returns a reversed copy
Ds\Sequence::rotate — Rotates the sequence by a given number of rotations
Ds\Sequence::set — Updates a value at a given index
Ds\Sequence::shift — Removes and returns the first value
Ds\Sequence::slice — Returns a sub-sequence of a given range
Ds\Sequence::sort — Sorts the sequence in-place
Ds\Sequence::sorted — Returns a sorted copy
Ds\Sequence::sum — Returns the sum of all values in the sequence
Ds\Sequence::unshift — Adds values to the front of the sequence