src/Container.php
public function offsetUnset($offset)
    {
        if (isset($this->map[$offset])) {
            unset($this->map[$offset]);
        }

        if (isset($this->services[$offset])) {
            unset($this->services[$offset]);
        }
    }
public function offsetUnset($offset)
    {
        if (isset($this->map[$offset])) {
            unset($this->map[$offset]);
        }

        if (isset($this->services[$offset])) {
            unset($this->services[$offset]);
        }
    }
Offset to unset

@link  http://php.net/manual/en/arrayaccess.offsetunset.php
@param mixed $offset <p>
The offset to unset.
</p>
@return void
@since 5.0.0