qiskit/circuit/instruction.py
def c_if(self, classical, val):
        """Add classical control on register classical and value val."""
        if not isinstance(classical, ClassicalRegister):
            raise QiskitError("c_if must be used with a classical register")
        if val < 0:
            raise QiskitError("control value should be non-negative")
        self.control = (classical, val)
        return self
def c_if(self, classical, val):
        """Add classical control on register classical and value val."""
        if not isinstance(classical, ClassicalRegister):
            raise QiskitError("c_if must be used with a classical register")
        if val < 0:
            raise QiskitError("control value should be non-negative")
        self.control = (classical, val)
        return self
Add classical control on register classical and value val.