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

from bu4.evaluation.constructs.eattachable import EAttachable
from bu4.evaluation.constructs.evaluable import Evaluable
from bu4.evaluation.constructs.etraceable import ETraceable
from bu4.linking.constructs.linked import Linked
from bu4.linking.evaluation.elvtype import elvtype
from bu4.linking.evaluation.lambdaelv import LambdaElv

__all__ = ('ELLambda',)


class ELLambda(ETraceable):
    def __init__(self, env: elvtype, name: bytes, value: Linked):
        self.env = env
        self.name = name
        self.value = value
        self.used = name in value.future
        self.memoize = name in value.multifuture

    def call(self, argument: Evaluable) -> Evaluable:
        return EAttachable(
            LambdaElv(self.env, self.name, argument, memoize=self.memoize) if self.used else self.env,
            self.value
        )

    def __str__(self):
        return f'({self.name.decode()}){self.value}'