from som.primitives.primitives import Primitives
from som.vmobjects.primitive   import Primitive 


def _holder(ivkbl, frame, interpreter):
    rcvr = frame.pop()
    frame.push(rcvr.get_holder())


def _signature(ivkbl, frame, interpreter):
    rcvr = frame.pop()
    frame.push(rcvr.get_signature())


class PrimitivePrimitives(Primitives):
    def install_primitives(self):
        self._install_instance_primitive(Primitive("holder",    self._universe, _holder))
        self._install_instance_primitive(Primitive("signature", self._universe, _signature))