Online PHP editor | output for e9odg

<?php $functionDef = <<<'EOF' <?php function notThisOne( $baz = 'boz') {} function foo ( Bar $bar, Baz $baz = 'string with, comma', $boz = ['something'] ) { } EOF; $function = 'foo'; $argument = 'baz'; if (!preg_match('/function\s+' . preg_quote($function) . '\s*$\s*(?P<args>.*?)$/is', $functionDef, $matches)) { throw new RuntimeException('Cound not find parameters for function ' . $function); } $tokens = token_get_all('<?php ' . $matches['args']); // small state machine, better in a class $foundArg = false; $default = ''; while ($token = next($tokens)) { // find the argument first of all if (!$foundArg) { if (is_array($token) && $token[1] == '$'.$argument) { $foundArg = true; } continue; } // detect when we have got to the end of the definitoin if ($token === ',') { break; } // compile everything else into the string if (is_string($token)) { $default .= $token; } else { $default .= $token[1]; } } var_dump($default);