php - Call a function within a function display both within array -

how call function within function?

function tt($data,$s,$t){     $data=$data;     echo '[[';     print_r($data);     echo ']]';     if($t==0){         $data[]=$s;         tt($data,'two',1);     }else{         $data[]=$s;     }     return $data; } print_r(tt('','one',0)); 

i want 'two' shown within array like

$o[]='one'; $o[]='two'; print_r($o); 

function tt($s, $t, array $data = array()) {     $data[] = $s;     if ($t == 0) {         $data = tt('two', 1, $data);     }     return $data; }  print_r(tt('one', 0)); 

this that's needed.

1. put array last argument , make optional, because don't need on initial call.
2. when calling tt recursively, need "catch" return data, otherwise recursive call nothing of lasting value.
3. no need else, since you're going append entry array no matter , don't need write twice.