Math operations

[thepabloaguilar]

Hello, I'm opening this issue to discuss about Math operations. I've had and initial idea!

Create an class, MathOperations or something like, it'll store all operations to be executed when __call__ is called! So the math operations from _Callable will return that class.
I've made a simple test without the class:

>>> import operation
>>> from lambdas import _fmap

>>> # _ + 1 - 10
>>> operations = [_fmap(operator.add)(None, 1), _fmap(operator.sub)(None, 10)]
>>> first_operation, *rest_operations = operations
>>> reduce(lambda partial_result, operation: operation(partial_result), rest_operations, first_operation(1))
-8

I was worried about the operations order, but Python does it for us!

>>> # If we have this `_ + 1 * 2`, the operations list should be like below
>>> operations = [_fmap(operator.add)(None, 3)]

Python deals with the operations order, we just have to store them.

[thepabloaguilar]

I've implemented a test:

class MathOperations:
    def __init__(self) -> None:
        self._operations = []

    def _add_operation(self, operation, other):
        self._operations.append(partial(operation, other))
        return self

    def __add__(self, other):
        return self._add_operation(operator.add, other)

    def __mul__(self, other):
        return self._add_operation(operator.mul, other)

    def __sub__(self, other):
        return self._add_operation(operator.sub, other)

    def __mod__(self, other):
        return self._add_operation(operator.mod, other)

    def __pow__(self, other):
        return self._add_operation(operator.pow, other)

    def __call__(self, number):
        first_operation, *rest_operations = self._operations
        return reduce(
            lambda partial_result, operation: operation(partial_result),
            rest_operations,
            first_operation(number)
        )


class _Callable(object):
    def __add__(self, other) -> Callable[['_Callable', T1], Callable[[T1], T1]]:
        return MathOperations() + other

>>> from lambdas import _

>>> func_one = _ + 1 * 10
>>> func_two = (_ + 1) * 10

>>> func_one(1)
1
>>> func_two(1)
20