array(3) {
[0]=>
string(2) "ba"
["a"]=>
string(1) "a"
[1]=>
string(1) "a"
}
bool(true)
Output for 5.2.0 - 5.2.1
Warning: preg_match(): Compilation failed: unrecognized character after (?< at offset 4 in /in/EPbVL on line 3
NULL
Warning: array_key_exists(): The second argument should be either an array or an object in /in/EPbVL on line 7
bool(false)