interp_Llambda.py

from ast import *
from interp_Lfun import InterpLfun, Function
from utils import *

class ClosureTuple(Value):
 __match_args__ = ("args", "arity")
 def __init__(self, args, arity):
 self.args = args
 self.arity = arity
 def __repr__(self):
 return 'ClosureTuple(' + repr(self.args) + ', ' + repr(self.arity) + ')'
 # TODO: move the following into interp_getitem and interp_setitem 
 def __getitem__(self, item):
 return self.args[item]
 def __setitem__(self, item, value):
 self.args[item] = value
 def __len__(self):
 return len(self.args)
 
class InterpLlambda(InterpLfun):

 def arity(self, v):
 match v:
 case Function(name, params, body, env):
 return len(params)
 case ClosureTuple(args, arity):
 return arity
 case _:
 raise Exception('Llambda arity unexpected ' + repr(v))
 
 def interp_exp(self, e, env):
 match e:
 case Call(Name('arity'), [fun]):
 f = self.interp_exp(fun, env)
 return self.arity(f)
 case Uninitialized(ty):
 return None
 case FunRef(id, arity):
 return env[id]
 case Lambda(params, body):
 return Function('lambda', params, [Return(body)], env)
 case UncheckedCast(exp, ty):
 return self.interp_exp(exp, env)
 case Closure(arity, args):
 return ClosureTuple([self.interp_exp(arg, env) for arg in args], arity)
 case AllocateClosure(length, typ, arity):
 array = [None] * length
 return ClosureTuple(array, arity)
 case _:
 return super().interp_exp(e, env)
 
 def interp_stmt(self, s, env, cont):
 match s:
 case AnnAssign(lhs, typ, value, simple):
 env[lhs.id] = self.interp_exp(value, env)
 return self.interp_stmts(cont, env)
 case Pass():
 return self.interp_stmts(cont, env)
 case _:
 return super().interp_stmt(s, env, cont)