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

from bu4.evaluation.av.envtype import envtype
from bu4.evaluation.constructs.elambda import ELambda
from bu4.evaluation.constructs.evaluable import Evaluable
from bu4.linking.constructs.linked import Linked

__all__ = ('LLambda',)


class LLambda(Linked):
    value: Linked

    def __init__(self, name: bytes, value: Linked):
        self.name = name
        self.value = value
        self.future = self.value.future - {name}
        self.multifuture = self.future
        self.used = name in value.future

    def evaluable(self, env: envtype) -> Evaluable:
        return ELambda(
            {name: env[name] for name in self.future} if self.used else env,
            self.name,
            self.value
        )

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