interp_Lvar.py

from ast import *
from utils import input_int
from interp_Lint import InterpLint

class InterpLvar(InterpLint):
  def interp_exp(self, e, env):
    match e:
      case Name(id):
        return env[id]
      case _:
        return super().interp_exp(e, env)

  def interp_stmts(self, ss, env):
    if len(ss) == 0:
      return
    match ss[0]:
      case Assign([lhs], value):
        env[lhs.id] = self.interp_exp(value, env)
        return self.interp_stmts(ss[1:], env)
      case _:
        return super().interp_stmts(ss, env)
        
  def interp(self, p):
    match p:
      case Module(body):
        self.interp_stmts(body, {})
      case _:
        raise Exception('interp: unexpected ' + repr(p))
    
if __name__ == "__main__":
  eight = Constant(8)
  neg_eight = UnaryOp(USub(), eight)
  read = Call(Name('input_int'), [])
  ast1_1 = BinOp(read, Add(), neg_eight)
  pr = Expr(Call(Name('print'), [ast1_1]))
  p = Module([pr])
  interp = InterpLvar()
  interp.interp_Lvar(p)