#  Copyright (c) PARRRATE T&V 2021. All rights reserved.

from typing import Sequence

from bu4.evaluation.av.evtype import evtype
from bu4.evaluation.constructs.evaluable import Evaluable
from bu4.evaluation.targets.avicontainer import AVIContainer

__all__ = ('LambdaEv',)


class LambdaEv(Sequence[Evaluable]):
    def __getitem__(self, i: int) -> Evaluable:
        if i == 0:
            return self.container
        else:
            return self.ev[i - 1]

    def __len__(self) -> int:
        return len(self.ev) + 1

    def __init__(self, ev: evtype, evaluable: Evaluable, *, memoize):
        self.ev = ev
        self.container = AVIContainer(evaluable).after_value if memoize else evaluable