from bu4.evaluation.elinked import ELinked
from bu4.evaluation.lambdaenv import LambdaEnv
from bu4.parsing.linked import Linked
from bu4.evaluation.aftervalue import EValue, envtype, Evaluable

__all__ = ('ELambda',)


class ELambda(EValue):
    def __init__(self, env: envtype, name: bytes, value: Linked):
        self.env = env
        self.name = name
        self.value = value

    def call(self, argument: Evaluable) -> Evaluable:
        return ELinked(
            LambdaEnv(self.env, self.name, argument),
            self.value
        )

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