<?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
 * @param array $arr2
 * @param array ...$arr3
 *
 * @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
 * @psalm-template TArray as array<TKey, mixed>
 *
 * @param TArray $arr
 *
 * @return (TArray is array<empty, empty> ? null : TKey|null)
 * @psalm-pure
 * @psalm-ignore-nullable-return
 */
function key($arr)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TArray as array<TKey, mixed>
 *
 * @param TArray $arr
 *
 * @return (TArray is array<empty, empty> ? null : (TArray is non-empty-array ? TKey : TKey|null))
 * @psalm-pure
 */
function array_key_first($arr)
{
}

/**
 * @psalm-template TKey as array-key
 * @psalm-template TArray as array<TKey, mixed>
 *
 * @param TArray $arr
 *
 * @return (TArray is array<empty, empty> ? null : (TArray is non-empty-array ? TKey : TKey|null))
 * @psalm-pure
 */
function array_key_last($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-pure
 *
 * @psalm-template K of array-key
 * @psalm-template T
 *
 * @param array<K,T> $arr
 *
 * @return array<K,T>
 */
function array_change_key_case(array $arr, int $case = CASE_LOWER)
{
}

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

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

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

/**
 * @psalm-pure
 *
 * @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)
 *
 * @psalm-taint-specialize
 * @psalm-flow ($var) -> return
 */
function var_export($var, bool $return = false) {}

/**
 * @param mixed $var
 * @param bool $return
 * @return ($return is true ? string : true)
 *
 * @psalm-taint-specialize
 * @psalm-flow ($var) -> return
 */
function print_r($var, bool $return = false) {}

/**
 * @psalm-pure
 *
 * @psalm-taint-sink file $var
 * @param mixed $var
 * @return ($return is true ? string : bool)
 */
function highlight_file($var, bool $return = false) {}

/**
 * @psalm-pure
 *
 * @psalm-taint-sink file $var
 * @param mixed $var
 * @return ($return is true ? string : bool)
 */
function show_source($var, bool $return = false) {}

/**
 * @psalm-pure
 *
 * @psalm-taint-sink file $filename
 */
function php_strip_whitespace(string $filename) : string {}

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

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

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

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

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

/**
 * @psalm-pure
 *
 * @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) {}

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

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

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

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

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function strtoupper(string $str) : string {}

/**
 * @psalm-pure
 *
 * @param string|array<string> $string
 * @param string|array<string> $replacement
 * @param int|array<int> $start
 * @param null|int|array<int> $length
 *
 * @return ($string is array<string> ? array<string> : string)
 *
 * @psalm-flow ($string, $replacement) -> return
 */
function substr_replace($string, $replacement, $start, $length = null) {}

/**
 * @psalm-pure
 *
 * @param string $haystack
 *
 * @psalm-return positive-int|0|false
 */
function strpos($haystack, $needle, int $offset = 0) : int {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function trim(string $str, string $character_mask = " \t\n\r\0\x0B") : string {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function ltrim(string $str, string $character_mask = " \t\n\r\0\x0B") : string {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function rtrim(string $str, string $character_mask = " \t\n\r\0\x0B") : string {}

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

/**
 * @psalm-pure
 *
 * @param string|array $glue
 *
 * @return (
 *     $glue is non-empty-string
 *     ? ($pieces is non-empty-array
 *         ? non-empty-string
 *         : string)
 *     : string
 * )
 *
 * @psalm-flow ($glue) -> return
 * @psalm-flow ($pieces) -(array-fetch)-> return
 */
function join($glue, array $pieces = []): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($string) -(array-assignment)-> return
 */
function explode(string $delimiter, string $string, int $limit = -1) : array {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($subject) -(array-assignment)-> return
 *
 * @template TFlags as int-mask<0, 1, 2, 4>
 *
 * @param TFlags $flags
 *
 * @return (TFlags is 0|2 ? non-empty-list<string>|false : (TFlags is 1|3 ? list<string>|false : list<array{string,int}>|false))
 *
 * @psalm-ignore-falsable-return
 */
function preg_split(string $pattern, string $subject, int $limit = -1, int $flags = 0) {}

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

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

/**
 * @psalm-pure
 *
 * @psalm-taint-escape html
 * @psalm-flow ($str) -> return
 */
function strip_tags(string $str, ?string $allowable_tags = null) : string {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function stripcslashes(string $str) : string {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function stripslashes(string $str) : string {}

/**
 * @psalm-pure
 *
 * @psalm-taint-escape html
 *
 * @psalm-flow ($string) -> return
 */
function htmlentities(string $string, ?int $quote_style = null, ?string $charset = null, bool $double_encode = true) : string {}

/**
 * @psalm-pure
 *
 * @psalm-taint-unescape html
 *
 * @psalm-flow ($string) -> return
 */
function html_entity_decode(string $string, ?int $quote_style = null, ?string $charset = null) : string {}

/**
 * @psalm-pure
 *
 * @psalm-taint-escape html
 * @psalm-taint-escape sql
 *
 * @psalm-flow ($string) -> return
 */
function htmlspecialchars(string $string, int $flags = ENT_COMPAT | ENT_HTML401, string $encoding = 'UTF-8', bool $double_encode = true) : string {}

/**
 * @psalm-pure
 *
 * @psalm-taint-unescape html
 * @psalm-taint-unescape sql
 *
 * @psalm-flow ($string) -> return
 */
function htmlspecialchars_decode(string $string, ?int $quote_style = null) : string {}

/**
 * @psalm-pure
 *
 * @param string|array<string|int|float> $search
 * @param string|array<string|int|float> $replace
 * @param string|array<string|int|float> $subject
 * @param int $count
 * @return ($subject is array ? array<string> : string)
 *
 * @psalm-flow ($replace, $subject) -> return
 */
function str_replace($search, $replace, $subject, &$count = null) {}

/**
 * @psalm-pure
 *
 * @param string|array<string|int|float> $search
 * @param string|array<string|int|float> $replace
 * @param string|array<string|int|float> $subject
 * @param int $count
 * @return ($subject is array ? array<string> : string)
 *
 * @psalm-flow ($replace, $subject) -> return
 */
function str_ireplace($search, $replace, $subject, &$count = null) {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($input, $pad_string) -> return
 */
function str_pad(string $input, int $pad_length, $pad_string = '', int $pad_type = STR_PAD_RIGHT): string {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($input) -> return
 */
function str_repeat(string $input, int $multiplier): string {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function str_rot13(string $str): string {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function str_shuffle(string $str): string {}

/**
 * @psalm-pure
 * @return ($split_length is positive-int ? list<string> : false)
 *
 * @psalm-flow ($string) -> return
 */
function str_split(string $string, int $split_length = 1) {}

/**
 * @psalm-pure
 * @return string|false
 * @psalm-ignore-falsable-return
 *
 * @psalm-flow ($haystack) -> return
 */
function strstr(string $haystack, string $needle, bool $before_needle = false) {}

/**
 * @psalm-pure
 * @return string|false
 * @psalm-ignore-falsable-return
 *
 * @psalm-flow ($haystack) -> return
 */
function stristr(string $haystack, string $needle, bool $before_needle = false) {}

/**
 * @psalm-pure
 * @return string|false
 * @psalm-ignore-falsable-return
 *
 * @psalm-flow ($haystack) -> return
 */
function strchr(string $haystack, string $needle, bool $before_needle = false) {}

/**
 * @psalm-pure
 * @return string|false
 * @psalm-ignore-falsable-return
 *
 * @psalm-flow ($haystack) -> return
 */
function strpbrk(string $haystack, string $char_list) {}

/**
 * @psalm-pure
 * @return string|false
 * @psalm-ignore-falsable-return
 *
 * @psalm-flow ($haystack) -> return
 */
function strrchr(string $haystack, string $needle) {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($string) -> return
 */
function strrev(string $string): string {}

/**
 * @psalm-pure
 *
 * @param string|string[] $pattern
 * @param string|array<string|int|float> $replacement
 * @param string|array<string|int|float> $subject
 * @param int $count
 * @return ($subject is array ? array<string> : string)
 *
 * @psalm-flow ($replacement, $subject) -> return
 */
function preg_filter($pattern, $replacement, $subject, int $limit = -1, &$count = null) {}

/**
 * @psalm-pure
 *
 * @param string|string[] $search
 * @param string|array<string|int|float> $replace
 * @param string|array<string|int|float> $subject
 * @param int $count
 * @return ($subject is array ? array<string>|null : string|null)
 *
 * @psalm-flow ($replace, $subject) -> return
 */
function preg_replace($search, $replace, $subject, int $limit = -1, &$count = null) {}

/**
 * @param string|string[] $search
 * @param callable(array<int, string>):string $replace
 * @param string|array<string|int|float> $subject
 * @param int $count
 * @return ($subject is array ? array<string>|null : string|null)
 *
 * @psalm-taint-specialize
 * @psalm-flow ($subject) -> return
 */
function preg_replace_callback($search, $replace, $subject, int $limit = -1, &$count = null) {}

/**
 * @psalm-pure
 * @template TFlags as int
 *
 * @param string $pattern
 * @param string $subject
 * @param mixed $matches
 * @param TFlags $flags
 * @param-out (
 *          TFlags is 1
 *          ? array<list<string>>
 *          : (TFlags is 2
 *              ? list<array<string>>
 *              : (TFlags is 256|257
 *                  ? array<list<array{string, int}>>
 *                  : (TFlags is 258
 *                      ? list<array<array{string, int}>>
 *                      : (TFlags is 512|513
 *                          ? array<list<?string>>
 *                          : (TFlags is 514
 *                              ? list<array<?string>>
 *                              : (TFlags is 770
 *                                  ? list<array<array{?string, int}>>
 *                                  : array
 *                              )
 *                          )
 *                      )
 *                  )
 *              )
 *          )
 *        ) $matches
 * @return int|false
 * @psalm-ignore-falsable-return
 */
function preg_match_all($pattern, $subject, &$matches = [], int $flags = 1, int $offset = 0) {}

/**
 * @psalm-pure
 *
 * @return (PHP_MAJOR_VERSION is 5|7 ? string|false : string)
 * @psalm-ignore-falsable-return
 *
 * @psalm-flow ($string) -> return
 */
function substr(string $string, int $start, ?int $length = null) {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function preg_quote(string $str, ?string $delimiter = null) : string {}

/**
 * @psalm-pure
 *
 * @param string|int|float $args
 *
 * @psalm-flow ($format, $args) -> return
 */
function sprintf(string $format, ...$args) : string {}

/**
 * @psalm-pure
 * @return string|false
 * @psalm-ignore-falsable-return
 *
 * @psalm-flow ($format, $args) -> return
 */
function vsprintf(string $format, array $args) {}

/**
 * @psalm-pure
 * @return string
 *
 * @psalm-flow ($str) -> return
 */
function wordwrap(string $str, int $width = 75, string $break = "\n", bool $cut = false) : string {}

/**
 * @psalm-pure
 *
 * @param string|int|float $values
 *
 * @psalm-flow ($format, $values) -> return
 */
function printf(string $format, ...$values) : string {}

/**
 * @psalm-pure
 *
 * @return string|false
 * @psalm-ignore-falsable-return
 *
 * @psalm-flow ($path) -> return
 */
function realpath(string $path) {}

/**
 * @psalm-pure
 *
 * @param numeric-string $left_operand
 * @param numeric-string $right_operand
 * @return ($right_operand is "0" ? null : numeric-string)
 */
function bcdiv(string $left_operand, string $right_operand, int $scale = 0): ?string {}

/**
 * @psalm-pure
 *
 * @param scalar|null|object $var
 * @return string The string value of var.
 *
 * @psalm-flow ($var) -> return
 */
function strval ($var): string {}

/**
 * @return ($input is non-empty-string ? non-empty-list<string> : non-empty-list<string>|array{null})
 * @psalm-pure
 *
 * @psalm-flow ($input) -> return
 */
function str_getcsv(string $input, string $delimiter = ',', string $enclosure = '"', string $escape = '\\\\')
{
}

/**
 * @return ($min is positive-int ? positive-int : int)
 */
function random_int(int $min, int $max): int {}

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

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function addcslashes(string $str, string $charlist) : string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function addslashes(string $str): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function ucfirst(string $str): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str, $delimiters) -> return
 */
function ucwords (string $str, string $delimiters = " \t\r\n\f\v"): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function lcfirst(string $str): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function nl2br(string $str, bool $is_xhtml = false): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function quoted_printable_decode(string $str): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function quoted_printable_encode(string $str): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function quotemeta(string $str): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($str) -> return
 */
function chop(string $str, string $character_mask = " \t\n\r\0\x0B"): string
{
}

/**
 * @psalm-pure
 * @psalm-flow ($str, $end) -> return
 */
function chunk_split(string $str, int $chunklen = 76, string $end= ''): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($data) -> return
 */
function convert_uudecode(string $data): string
{
}

/**
 * @psalm-pure
 *
 * @psalm-flow ($data) -> return
 */
function convert_uuencode(string $data) : string
{
}

/**
 * @psalm-pure
 *
 * @psalm-taint-escape ldap
 * @psalm-flow ($value) -> return
 */
function ldap_escape(string $value, string $ignore = "", int $flag = 0) : string {}

/**
 * @psalm-pure
 *
 * @return mixed
 * @psalm-flow ($json) -> return
 */
function json_decode(string $json, ?bool $associative = null, int $depth = 512, int $flags = 0) {}

/**
 * @psalm-pure
 *
 * @return string|false
 *
 * @psalm-flow ($value) -> return
 * @psalm-ignore-falsable-return
 */
function json_encode(mixed $value, int $flags = 0, int $depth = 512) {}

/**
 * @psalm-pure
 *
 * @return string|false
 *
 * @psalm-flow ($values) -> return
 * @psalm-ignore-falsable-return
 */
function pack(string $format, mixed ...$values) {}

/**
 * @psalm-pure
 *
 * @param string|int $in_codepage
 * @param string|int $out_codepage
 * @psalm-flow ($subject) -> return
 */
function sapi_windows_cp_conv($in_codepage, $out_codepage, string $subject) : string {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($prefix) -> return
 */
function uniqid(string $prefix = "", bool $more_entropy = false) : string {}

/**
 * @psalm-pure
 *
 * @return array
 *
 * @psalm-flow ($data) -> return
 */
function unpack(string $format, string $data, int $offset = 0) {}

/**
 * @psalm-pure
 *
 * @return string|false
 *
 * @psalm-flow ($data) -> return
 * @psalm-ignore-falsable-return
 */
function base64_decode(string $data, bool $strict = false) {}

/**
 * @psalm-pure
 *
 * @psalm-flow ($data) -> return
 */
function base64_encode(string $data) : string {}

/**
 * @psalm-pure
 *
 * @param resource|null $context
 *
 * @psalm-taint-sink ssrf $url
 */
function get_headers(string $url, int $format = 0, $context = null) : array {}

/**
 * @psalm-pure
 *
 * @psalm-taint-sink ssrf $filename
 */
function get_meta_tags(string $filename, bool $use_include_path = false) : array {}