A simple Stack Machine VM created for the Python's Workshop that I I'll teach.

calc-stack-vm.py

"""
Copyright 2024 RickBarretto

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""

from operations2 import ops

# mostrar uso do assing
# mostrar no quadro como funciona uma lista, e quais seus principais métodos
stack = []
# demosntrar exemplos de variáveis booleanas
running = True

while running:
    print("Stack ops: [push / pop / show]")
    print("Math ops: [add / sub / mul / div]")

    # explicar string
    # explicar input
    # explicar strip
    # explicar split
    op, *values = input(">> ").strip().split(" ")
    values = [int(value) for value in values]
    
    # fazer usando if-else primeiro, sem uso de dicionários
    #  * chama-se cada função dentro do if-else (fazer push, pop e add)
    # fazer usando for-loop primeiro
    #  * fazer sub e end
    # colocar funções em outro módulo
    # explicar importing
    # refatorar para list-comprehension
    # refatorar módulo operations para usar classes
    # usar try-except aqui para finalizar
    try:
        operation_function = ops[op]
        operation_function(stack, values)
        print()
    except KeyError:
        print("Comando digitado não existe.")

operations.py

"""
Copyright 2024 RickBarretto

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""

# ao final, remover duplicação de código usando essas funções
def _show_needed_stack_size(needed_size: int):
    print(f"Sua stack é insuficiente. São necessários {needed_size} valores para a operação.")
    print("Dica: use o comando 'push' para inserir elementos na stack.")

def _show_command_does_not_get_args(command: str):
    print(f"O comando '{command}' não recebe argumentos.")



# primeiro escreva as funções como:
#
# def pop(stack, *values):
#     if values:
#         print("Sua stack é insuficiente. São necessários 2 valores para a operação.")
#         print("Dica: use o comando 'push' para inserir elementos na stack.")
#         return
#
#     if not stack:
#         print("O comando 'pop' não recebe argumentos.")
#         return
#
#     print(stack.pop())
#
# usando o dicionário:
#
# ops = {
#     "end": end,
#     "show": show,
#     "push": push,
#     "pop": pop,
#     "add": add,
#     "sub": sub,
#     "mul": mul,
#     "div": div,
# }

# depois escreva as funções como:
#
# def pop(stack, *values):
#     if values:
#         _show_command_does_not_get_args("pop")
#         return
#
#     if not stack:
#         _show_needed_stack_size(1)
#         return
#
#     print(stack.pop())


def end(stack, values):
    if values:
        _show_command_does_not_get_args("end")
        return
    
    exit()


def show(stack, values):
    if values:
        _show_command_does_not_get_args("show")
        return
    
    print(stack)


def push(stack, values):
    for value in values:
        stack.append(value)


def pop(stack, values):
    if values:
        _show_command_does_not_get_args("pop")
        return

    if not stack:
        _show_needed_stack_size(1)
        return

    print(stack.pop())


def add(stack, values):
    if values:
        _show_command_does_not_get_args("add")
        return

    if len(stack) < 2:
        _show_needed_stack_size(2)
        return

    a, b = stack.pop(), stack.pop()
    push(stack, a + b)


def sub(stack, values):
    if values:
        _show_command_does_not_get_args("sub")
        return

    if len(stack) < 2:
        _show_needed_stack_size(2)
        return

    b, a = stack.pop(), stack.pop()
    push(stack, a - b)


def mul(stack, values):
    if values:
        _show_command_does_not_get_args("mul")
        return
    
    if len(stack) < 2:
        _show_needed_stack_size(2)
        return
    
    b, a = stack.pop(), stack.pop()
    push(stack, a * b)


def div(stack, values):
    if values:
        _show_command_does_not_get_args("div")
        return
    
    if len(stack) < 2:
        _show_needed_stack_size(2)
        return
    
    b, a = stack.pop(), stack.pop()

    if b == 0:
        print("Divisão por 0 não permitida.")
        push(stack, a, b)
        return

    push(stack, a / b)


ops = {
    "end": end,
    "show": show,
    "push": push,
    "pop": pop,
    "add": add,
    "sub": sub,
    "mul": mul,
    "div": div,
}

operations2.py

"""
Copyright 2024 RickBarretto

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""

# ao final, remover duplicação de código 
# usando classes

from typing import Any

# Mostrar criação da classe base
class Command:

    def __init__(self, command: str, arity: int, has_args: bool) -> None:
        self.command: str = command
        self.arity: int = arity
        self.has_args: int = has_args

    def match_requisites(self, stack, args):
        if args and not self.has_args:
            self.show_cant_get_params()
            return False

        if len(stack) < self.arity:
            self.show_insufficient_stack()
            return False
        
        return True

    def show_insufficient_stack(self):
        print("Sua stack é insuficiente.",
              f"São necessários {self.arity} valores para a operação '{self.command}'.")
        print("Dica: use o comando 'push' para inserir elementos na stack.")

    def show_cant_get_params(self):
        print(f"O comando '{self.command}' não recebe argumentos.")

    def __call__(self, stack: list[int], args: list[int]) -> Any:
        if self.match_requisites(stack, args):
            self.operate(stack, args)
        

# Mostrar criação das classes filhas

class End(Command):
    # Desafio final: criar função help e menu help.
    def help(self) -> str:
        return "Finaliza o programa..."

    def operate(self, stack: list[int], args):
        exit()

class Show(Command):
    def operate(self, stack: list[int], args):
        print(stack)

class Push(Command):
    def operate(self, stack: list[int], args):
        stack.extend(args)

class Pop(Command):
    def operate(self, stack: list[int], args):
        print(stack.pop())

class Add(Command):
    def operate(self, stack: list[int], args):
        a, b = stack.pop(), stack.pop()
        stack.append(a + b)

class Sub(Command):
    def operate(self, stack: list[int], args):
        a, b = stack.pop(), stack.pop()
        stack.append(a - b)

class Mul(Command):
    def operate(self, stack: list[int], args):
        a, b = stack.pop(), stack.pop()
        stack.append(a * b)

class Div(Command):
    def operate(self, stack: list[int], args):
        b, a = stack.pop(), stack.pop()

        try:
            stack.append(a / b)
        except ZeroDivisionError:
            print("Divisão por 0 não permitida.")
            stack.extend([a, b])

# Mostrar criação das instâncias
# usando o seguinte dicionário  
# ops = {
#     "end": End("end", 0, False),
#     "show": Show("show", 0, False),
#     "push": Push("push", 0, True),
#     "pop": Pop("pop", 1, False),
#     "add": Add("add", 2, False),
#     "sub": Sub("sub", 2, False),
#     "mul": Mul("mul", 2, False),
#     "div": Div("div", 2, False),
# }

# então
operations = [
    End("end", 0, False),
    Show("show", 0, False),
    Push("push", 0, True),
    Pop("pop", 1, False),
    Add("add", 2, False),
    Sub("sub", 2, False),
    Mul("mul", 2, False),
    Div("div", 2, False), 
]

ops = {operation.command: operation for operation in operations}