array.php
Useful array methods for PHP
use duzun\ArrayClass as AC;
Methods
::to_array
Try to convert a value into Array, or return the value when can't convert.
ArrayClass::to_array($object, $recursive=false)
The $object
can be a Generator
, Traversable
or any object which has a ::getArrayCopy()
method.
Examples
AC::to_array(1); // [1]
AC::to_array((function() { yield 1; })()); // [1]
AC::to_array(new \ArrayObject([1,2,3])); // [1,2,3]
AC::to_array($o = new class {}); // $o - don't know how to convert :(
::is_assoc
Check whether an array is associative or not (indexed?).
ArrayClass::is_assoc($array, $strict = true): bool
Examples
AC::is_assoc(['a','b','c']) === false;
AC::is_assoc([1 => 'a', 2 => 'b', 3 => 'c']) === true;
AC::is_assoc([1 => 'a', 2 => 'b', 3 => 'c'], false) === false;
AC::is_assoc(['x' => 'a', 2 => 'b', 3 => 'c'], false) === true;
::repeat
Repeat the values of an array a number of times (array_fill()
on steroids).
ArrayClass::repeat(array $array, int $times): array
Examples
// the most trivial case, same as array_fill(0, 3, 1);
AC::repeat([1], 3) === [1,1,1];
AC::repeat([1,2], 2) === [1,2,1,2];
// $times has to be positive
AC::repeat([1], 0) === [];
AC::repeat([1], -5) === [];
// doesn't preserve keys, ever
AC::repeat(['a' => 1, 'b' => 2, 'c' => 3], 3) === [1,2,3,1,2,3,1,2,3];
AC::repeat(['a' => 1, 'b' => 2, 'c' => 3], 1) === [1,2,3];
::cyclic_slice
Like array_slice()
, only cyclic, as if the array was a ring and we can slice from any point any number of items, sequentially.
ArrayClass::cyclic_slice(
array $array,
int $offset,
int $length = NULL,
bool $preserve_keys = false
): array
Examples
AC::cyclic_slice(['a','b','c','d','e'], 1) === ['b','c','d','e','a']; // rotate by 1
AC::cyclic_slice(['a','b','c','d','e'], -1) === ['e','a','b','c','d']; // rotate by -1
AC::cyclic_slice(['a','b','c','d','e'], 1, 2) === ['b','c']; // slice 2 items
AC::cyclic_slice(['a','b','c','d','e'], 1, -2) === ['b','a']; // slice 2 items in reverse
// slice, while cycling, to fulfill the length
AC::cyclic_slice(['a','b','c','d'], 3, 9) === ['d','a','b','c','d','a','b','c','d'];
AC::cyclic_slice(['a','b','c','d'], -3, -9) === ['b','a','d','c','b','a','d','c','b'];
// preserve keys
AC::cyclic_slice(['a'=>1, 'b'=>2, 'c'=>3, 'd'=>4], 3, 3) === ['d'=>4, 'a'=>1, 'b'=>2];
::id
Given a list of items by IDs, get a new ID that doesn't exist in the list.
ArrayClass::id($array): int
Examples
AC::id( NULL ) === 1;
AC::id( [1] ) === 1;
AC::id( [2=>1] ) === 3;
AC::id( [9=>0, 10=>1, 11=>2] ) === 12;
::group
Group array items of an array by a list of fields.
ArrayClass::group($list, $fields, $as_list = false): array
Examples
// Given an array of arrays:
$array = [
[ 'a' => 1, 'b' => 3, 'c' => 7 ],
[ 'a' => 1, 'b' => 3, 'c' => 8 ],
[ 'a' => 1, 'b' => 5, 'c' => 9 ],
[ 'a' => 2, 'b' => 3, 'c' => 10 ],
[ 'a' => 2, 'b' => 5, 'c' => 11 ],
[ 'a' => 2, 'b' => 5, 'c' => 11 ],
];
// group by values of field 'a', preserving the last appearance
AC::group($array, ['a']) == [
1 => [ 'a' => 1, 'b' => 5, 'c' => 9 ],
2 => [ 'a' => 2, 'b' => 5, 'c' => 11 ],
];
// group by values of field 'a', preserving all items by adding an extra level of depth.
AC::group($array, ['a'], true) == [
1 => [
[ 'a' => 1, 'b' => 3, 'c' => 7 ],
[ 'a' => 1, 'b' => 3, 'c' => 8 ],
[ 'a' => 1, 'b' => 5, 'c' => 9 ],
],
2 => [
[ 'a' => 2, 'b' => 3, 'c' => 10 ],
[ 'a' => 2, 'b' => 5, 'c' => 11 ],
[ 'a' => 2, 'b' => 5, 'c' => 11 ],
],
];
// group by two fields, preserving the last appearance
AC::group($array, ['a', 'b'], false) == [
1 => [
3 => [ 'a' => 1, 'b' => 3, 'c' => 8 ],
5 => [ 'a' => 1, 'b' => 5, 'c' => 9 ],
],
2 => [
3 => [ 'a' => 2, 'b' => 3, 'c' => 10 ],
5 => [ 'a' => 2, 'b' => 5, 'c' => 11 ],
],
];
code and test files.
See other methods in the@TODO test and document everything else