public function offsetSet($offset, $value)
    {
        if (is_null($offset)) {
            throw new \Exception('Must supply key to modify an associative array.');
        } else {
            if ($this->_isFillable($offset)) {
                $this->_args[$offset] = $value;
            } else {
                throw new \Exception('Cannot modify element \''.$offset.'\'. Not fillable.');
            }
        }
    }
public function offsetSet($offset, $value)
    {
        if (is_null($offset)) {
            throw new \Exception('Must supply key to modify an associative array.');
        } else {
            if ($this->_isFillable($offset)) {
                $this->_args[$offset] = $value;
            } else {
                throw new \Exception('Cannot modify element \''.$offset.'\'. Not fillable.');
            }
        }
    }
public function offsetSet ( $ offset , $ value ) { if ( is_null ( $ offset ) ) { throw new \ Exception ( 'Must supply key to modify an associative array.' ) ; } else { if ( $ this -> _isFillable ( $ offset ) ) { $ this -> _args [ $ offset ] = $ value ; } else { throw new \ Exception ( 'Cannot modify element \'' . $ offset . '\'. Not fillable.' ) ; } } }
Override the offsetSet function to enforce
the list of restricted keys.

@param  mixed $offset
@param  mixed $value
@throws \Exception
Override the offsetSet function to enforce the list of restricted keys .