<?php
/**
 * @psalm-template TKey as array-key
 * @psalm-template TArray as array<TKey, mixed>
 *
 * @param TArray $arr
 * @param mixed $search_value
 * @param bool  $strict
 *
 * @return (TArray is non-empty-array ? non-empty-list<TKey> : list<TKey>)
 * @psalm-pure
 */
function array_keys(array $arr, $search_value = null, bool $strict = false)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey, TValue> $arr
 * @param array $arr2
 * @param array ...$arr3
 *
 * @return array<TKey, TValue>
 * @psalm-pure
 */
function array_intersect(array $arr, array $arr2, array ...$arr3)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey, TValue> $arr
 * @param array $arr2
 * @param array ...$arr3
 *
 * @return array<TKey, TValue>
 * @psalm-pure
 */
function array_intersect_key(array $arr, array $arr2, array ...$arr3)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey, TValue> $arr
 *
 * @return array<TKey, TValue>
 * @psalm-pure
 */
function array_intersect_assoc(array $arr, array $arr2, array ...$arr3)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<mixed, TKey> $arr
 * @param array<mixed, TValue> $arr2
 *
 * @return array<TKey, TValue>|false
 * @psalm-ignore-falsable-return
 * @psalm-pure
 */
function array_combine(array $arr, array $arr2)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey, TValue> $arr
 * @param array $arr2
 * @param array ...$arr3
 *
 * @return array<TKey, TValue>
 * @psalm-pure
 */
function array_diff(array $arr, array $arr2, array ...$arr3)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey, TValue> $arr
 * @param array $arr2
 * @param array ...$arr3
 *
 * @return array<TKey, TValue>
 * @psalm-pure
 */
function array_diff_key(array $arr, array $arr2, array ...$arr3)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey, TValue> $arr
 * @param array $arr2
 * @param array ...$arr3
 *
 * @return array<TKey, TValue>
 * @psalm-pure
 */
function array_diff_assoc(array $arr, array $arr2, array ...$arr3)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey, TValue> $arr
 *
 * @return array<TValue, TKey>
 * @psalm-pure
 */
function array_flip(array $arr)
{
}

/**
 * @psalm-template TKey as array-key
 *
 * @param array<TKey, mixed> $arr
 *
 * @return TKey|null
 * @psalm-ignore-nullable-return
 * @psalm-pure
 */
function key($arr)
{
}

/**
 * @psalm-template TKey as array-key
 *
 * @param array<TKey, mixed> $arr
 *
 * @return TKey|null
 * @psalm-ignore-nullable-return
 * @psalm-pure
 */
function array_key_first($arr)
{
}

/**
 * @psalm-template TKey as array-key
 *
 * @param array<TKey, mixed> $arr
 *
 * @return TKey|null
 * @psalm-ignore-nullable-return
 * @psalm-pure
 */
function array_key_last($arr)
{
}

/**
 * @psalm-template T
 *
 * @param mixed           $needle
 * @param array<T, mixed> $haystack
 * @param bool            $strict
 *
 * @return T|false
 * @psalm-pure
 */
function array_search($needle, array $haystack, bool $strict = false)
{
}

/**
 * @psalm-template T
 *
 * @param T[] $arr
 * @param-out list<T> $arr
 */
function shuffle(array &$arr): bool
{
}

/**
 * @psalm-template T
 *
 * @param T[] $arr
 * @param-out list<T> $arr
 */
function sort(array &$arr, int $sort_flags = SORT_REGULAR): bool
{
}

/**
 * @psalm-template T
 *
 * @param T[] $arr
 * @param-out list<T> $arr
 */
function rsort(array &$arr, int $sort_flags = SORT_REGULAR): bool
{
}

/**
 * @psalm-template T
 *
 * @param T[] $arr
 * @param callable(T,T):int $callback
 * @param-out list<T> $arr
 */
function usort(array &$arr, callable $callback): bool
{
}

/**
 * @psalm-template TKey
 * @psalm-template T
 *
 * @param array<TKey,T> $arr
 * @param callable(T,T):int $callback
 * @param-out array<TKey,T> $arr
 */
function uasort(array &$arr, callable $callback): bool
{
}

/**
 * @psalm-template TKey
 * @psalm-template T
 *
 * @param array<TKey,T> $arr
 * @param callable(TKey,TKey):int $callback
 * @param-out array<TKey,T> $arr
 */
function uksort(array &$arr, callable $callback): bool
{
}

/**
 * @psalm-template K of array-key
 * @psalm-template T
 *
 * @param array<K,T> $arr
 *
 * @return array<K,T>
 * @psalm-pure
 */
function array_change_key_case(array $arr, int $case = CASE_LOWER)
{
}

/**
 * @psalm-template TKey as array-key
 *
 * @param TKey $key
 * @param array<TKey, mixed> $search
 *
 * @return bool
 * @psalm-pure
 */
function array_key_exists($key, array $search) : bool
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey, TValue> $arr
 * @param array<TKey, TValue> ...$arr2
 *
 * @return array<TKey, TValue>
 * @psalm-pure
 */
function array_merge_recursive(array $arr, array ...$arr2)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TValue
 *
 * @param array<TKey> $keys
 * @param TValue $value
 *
 * @return array<TKey, TValue>
 * @psalm-pure
 */
function array_fill_keys(array $keys, $value): array
{
}

/**
 * @psalm-template TKey
 *
 * @param string $pattern
 * @param array<TKey,string> $input
 * @param 0|1 $flags 1=PREG_GREP_INVERT
 * @return array<TKey,string>
 */
function preg_grep($pattern, array $input, $flags = 0)
{
}

/**
 * @param resource $handle
 * @param-out closed-resource $handle
 */
function fclose(&$handle) : bool
{
}

/**
 * @param string $reference
 * @param-out null $reference
 */
function sodium_memzero(string &$reference): void
{
}

/**
 * @param mixed $var
 * @param bool $return
 * @return ($return is true ? string : void)
 */
function var_export($var, bool $return = false) {}

/**
 * @param mixed $var
 * @param bool $return
 * @return ($return is true ? string : true)
 */
function print_r($var, bool $return = false) {}

/**
 * @param mixed $var
 * @return ($return is true ? string : bool)
 */
function highlight_file($var, bool $return = false) {}

/**
 * @param mixed $var
 * @return ($return is true ? string : bool)
 */
function highlight_string($var, bool $return = false) {}

/**
 * @return ($get_as_float is true ? float : string)
 */
function microtime(bool $get_as_float = false) {}

/**
 * @return ($return_float is true ? float : array<string, int>)
 */
function gettimeofday(bool $return_float = false) {}

/**
 * @param numeric $number
 * @return ($number is int ? int : ($number is float ? float : int|float))
 */
function abs($number) {}

/**
 * @template T as string|int|float
 * @template TStep as int|float
 * @param T $start
 * @param T $end
 * @param TStep $step
 * @return (
 *     T is int
 *     ? (TStep is int ? list<int> : list<int|float>)
 *     : (
 *         T is float
 *         ? list<float>
 *         : (
 *              T is string
 *              ? list<string>
 *              : (
 *                   T is int|float
 *                   ? list<int|float>
 *                   : list<int|float|string>
 *              )
 *         )
 *     )
 * )
 */
function range($start, $end, $step = 1) {}

/**
 * @return (
 *     $format is 'd'|'j'|'N'|'w'|'z'|'W'|'m'|'n'|'t'|'L'|'o'|'Y'|'y'|'B'|'g'|'G'|'h'|'H'|'i'|'s'|'u'|'v'|'Z'|'U'|'I'
 *     ? numeric-string
 *     : ($timestamp is numeric ? string : string|false)
 * )
 */
function date(string $format, int $timestamp = 0) {}

/**
 * @param mixed $vars
 * @param-out string|int|float $vars
 * @return (func_num_args() is 2 ? list<float|int|string> : int)
 */
function sscanf(string $str, string $format, &...$vars) {}

/**
 * @return (
 *     func_num_args() is 1
 *     ? array{dirname: string, basename: string, extension?: string, filename: string}
 *     : string
 * )
 */
function pathinfo(string $path, int $options = \PATHINFO_DIRNAME) {}

/**
 * @template T as scalar
 * @template TFirstArg as array<T>|T
 *
 * @param TFirstArg $arg_1
 * @param T $arg_2
 *
 * @return T
 */
function min($arg_1, ...$arg_2) {}

/**
 * @template T as scalar
 * @template TFirstArg as array<T>|T
 *
 * @param TFirstArg $arg_1
 * @param T $arg_2
 *
 * @return T
 */
function max($arg_1, ...$arg_2) {}

/**
 * @return (func_num_args() is 0 ? array<string, string> : string|false)
 */
function getenv(string $varname = '', bool $local_only = false) {}

/**
 * @return (
 *     $str is non-empty-string ? non-empty-lowercase-string : lowercase-string
 * )
 */
function strtolower(string $str) : string {}

/**
 * @param string|array $glue
 *
 * @return (
 *     $glue is non-empty-string
 *     ? ($pieces is non-empty-array
 *         ? non-empty-string
 *         : string)
 *     : string
 * )
 */
function implode($glue, array $pieces = []) : string {}

/**
 * @param array $input
 *
 * @return (
 *     $input is array<int> 
 *     ? int 
 *     : ($input is array<float>
 *         ? float
 *         : float|int
 *     )
 * )
 */
function array_sum(array $input) {}