Interpreter

from enum import Enum
from sys import argv

OP = Enum('Op', 'PUSH SUM MULT SUB DIV PRINT')

if len(argv) > 1:
    filename = argv[1]
else:
    filename = "test"
try:
    file = open(filename, 'r')
except:
    print("Erro ao abrir arquivo.")
    quit()
filelines = file.read().split('\n')
file.seek(0)
fileread = file.read().split()
i = 0

isPush = False
isFirst = True
acc = 0

pilha = []
try:
    for exp in fileread:
        #print("Exp: [{}]".format(exp))
        #print("Line: {}".format(filelines[i]))
        if isPush:
            if exp.isnumeric():
                pilha.append(int(exp))
                isPush = False
                i+=1
                continue
            else:
                raise Exception()
        op = OP[exp]
        if op == OP.PUSH:
            isPush = True
            continue
        elif op == OP.PRINT:
            print(acc)
        elif op == OP.SUM:
            if isFirst:
                acc = pilha.pop() + pilha.pop()
                isFirst = False
            else:
                acc += pilha.pop()
        elif op == OP.MULT:
            if isFirst:
                acc = pilha.pop() * pilha.pop()
                isFirst = False
            else:
                acc *= pilha.pop()
        elif op == OP.SUB:
            if isFirst:
                acc = pilha.pop()
                isFirst = False
            acc = pilha.pop() - acc
        elif op == OP.DIV:
            if isFirst:
                acc = pilha.pop()
                isFirst = False
            acc = pilha.pop() / acc

        """
        match op:
            case OP.PUSH:
                isPush = True
                continue
            case OP.PRINT:
                print(acc)
            case OP.SUM:
                if isFirst:
                    acc = pilha.pop() + pilha.pop()
                    isFirst = False
                else:
                    acc += pilha.pop()
            case OP.MULT:
                if isFirst:
                    acc = pilha.pop() * pilha.pop()
                    isFirst = False
                else:
                    acc *= pilha.pop()
            case OP.SUB:
                if isFirst:
                    acc = pilha.pop()
                    isFirst = False
                acc = pilha.pop() - acc
            case OP.DIV:
                if isFirst:
                    acc = pilha.pop()
                    isFirst = False
                acc = pilha.pop() / acc
        """
        i+=1
except:
    print("Erro na linha: \"{}\"".format(filelines[i]))