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wp-includes/compat.php ›

WordPress implementation for PHP functions either missing from older PHP versions or not included by default.

Function Short description
hash_equalsTiming attack safe string comparison
hash_hmacCompat function to mimic hash_hmac().
is_countablePolyfill for is_countable() function added in PHP 7.3.
is_iterablePolyfill for is_iterable() function added in PHP 7.1.
mb_strlenCompat function to mimic mb_strlen().
mb_substrCompat function to mimic mb_substr().
_hash_hmacInternal compat function to mimic hash_hmac().
_mb_strlenInternal compat function to mimic mb_strlen().
_mb_substrInternal compat function to mimic mb_substr().
_wp_can_use_pcre_uReturns whether PCRE/u (PCRE_UTF8 modifier) is available for use.