def __str__(self):
function = str(self.operator)
args = '(' + comma_separated(self.operands) + ')'
if isinstance(self.operands, LambdaExpr):
return '(' + function + ')' + args
else:
return function + args
def apply(self, arguments):
"""
将参数绑定到lambda 的 变量中。
:param arguments:
:return:
"""
if len(self.parameters) != len(arguments):
raise TypeError(
"Cannot match parameters {} to arguments {}".format(
comma_separated(self.parameters), arguments))
env = self.parent.copy()
for p, a in zip(self.parameters, arguments):
env[p] = a
return self.body.eval(env)
def __str__(self):
body = str(self.body)
if not self.parameters:
return 'lambda: ' + body
else:
return 'lambda ' + comma_separated(body)
def __repr__(self):
args = '(' + comma_separated([repr(a) for a in self.args]) + ')'
return type(self).__name__ + args
def apply(self, arguments):
for a in arguments:
if not isinstance(a, Number):
raise TypeError("Invalid argument {} to {}".format(
comma_separated(arguments), self))
return Number(self.operator(*[a.value for a in arguments]))
def apply(self, arguments):
raise TypeError("Cannot apply number{} to arguments {}".format(
self.value, comma_separated(arguments)))