builtup4/bu4/evaluation/av/aftervalue.py

40 lines
1.4 KiB
Python

# Copyright (c) PARRRATE T&V 2021. All rights reserved.
from bu4.evaluation.constructs.evaluable import Evaluable
from bu4.evaluation.constructs.evalue import EValue
from bu4.evaluation.targets.avtarget import AVTarget
__all__ = ('AfterValue',)
class AfterValue(Evaluable):
def __init__(self, evaluable: Evaluable, target: AVTarget):
self.evaluable = evaluable
self.target = target
def next(self) -> Evaluable:
if isinstance(self.evaluable, EValue):
if isinstance(self.target, AVChain):
self.evaluable, self.target = self.target.target.given(self.evaluable), self.target.aftertarget
return self
return self.target.given(self.evaluable)
if isinstance(self.evaluable, AfterValue):
self.evaluable, self.target = self.evaluable.evaluable, AVChain(self.evaluable.target, self.target)
self.evaluable = self.evaluable.next()
return self
def __str__(self):
return f'{self.evaluable}->{self.target}'
class AVChain(AVTarget):
def __init__(self, target: AVTarget, aftertarget: AVTarget):
self.target = target
self.aftertarget = aftertarget
def given(self, value: EValue) -> Evaluable:
return AfterValue(self.target.given(value), self.aftertarget)
def __str__(self):
return f'{self.target}->{self.aftertarget}'