public function arrayStringKeys(Array_ $array)
    {
        $keys = [];
        foreach ($array->items as $item) {
            if ($item->key instanceof String_) {
                $keys[] = $item->key->value;
            }
        }

        return $keys;
    }
public function arrayStringKeys(Array_ $array)
    {
        $keys = [];
        foreach ($array->items as $item) {
            if ($item->key instanceof String_) {
                $keys[] = $item->key->value;
            }
        }

        return $keys;
    }
public function arrayStringKeys ( Array_ $ array ) { $ keys = [ ] ; foreach ( $ array -> items as $ item ) { if ( $ item -> key instanceof String_ ) { $ keys [ ] = $ item -> key -> value ; } } return $ keys ; }
Given an array, find all the string keys.

@param Array_ $array

@return array
Given an array find all the string keys .