--TEST-- preg_* with bogus vals --FILE-- getMessage() . "\n"; } var_dump(preg_quote('')); var_dump(preg_replace('/(.)/', '${1}${1', 'abc')); var_dump(preg_replace('/.++\d*+[/', 'for ($', 'abc')); var_dump(preg_replace('/(.)/e', 'for ($', 'abc')); ?> --EXPECTF-- preg_match_all(): Argument #4 ($flags) must be a PREG_* constant string(0) "" string(12) "a${1b${1c${1" Warning: preg_replace(): Compilation failed: missing terminating ] for character class at offset 8 in %s002.php on line %d NULL Warning: preg_replace(): Unknown modifier 'e' in %s on line %d NULL