public function withExtensions(Extensions $extensions): self
    {
        $obj = clone $this;
        $obj->_extensions = $extensions;
        return $obj;
    }
public function withExtensions(Extensions $extensions): self
    {
        $obj = clone $this;
        $obj->_extensions = $extensions;
        return $obj;
    }
public function withExtensions ( Extensions $ extensions ) : self { $ obj = clone $ this ; $ obj -> _extensions = $ extensions ; return $ obj ; }
Get self with extensions.

@param Extensions $extensions
@return self
Get self with extensions .