src/AbstractCollectionPlus.php
public function exists($func)
    {
        if (!is_callable($func, false, $callable_name))
            throw new \InvalidArgumentException(get_class($this).'::exists - Un-callable "$func" value seen!');

        foreach($this->_storage as $key => $value)
        {
            if (call_user_func($func, $key, $value))
                return true;
        }

        return false;
    }
public function exists($func)
    {
        if (!is_callable($func, false, $callable_name))
            throw new \InvalidArgumentException(get_class($this).'::exists - Un-callable "$func" value seen!');

        foreach($this->_storage as $key => $value)
        {
            if (call_user_func($func, $key, $value))
                return true;
        }

        return false;
    }
public function exists ( $ func ) { if ( ! is_callable ( $ func , false , $ callable_name ) ) throw new \ InvalidArgumentException ( get_class ( $ this ) . '::exists - Un-callable "$func" value seen!' ) ; foreach ( $ this -> _storage as $ key => $ value ) { if ( call_user_func ( $ func , $ key , $ value ) ) return true ; } return false ; }
Custom "contains" method

@param callable $func
@throws \InvalidArgumentException
@return bool
Custom contains method