Overload all operators

[cgarciae]

Hey, awesome library! I am new to nim and was trying out some basic python integration with nimpy, I am impressed :D

I was wondering if we could try to overload all operators for PyObject so basic stuff like addition and subtraction work out of the box. Currently I managed to do it like this:

import nimpy

let operator = pyImport("operator")
let np = pyImport("numpy")

proc `+`(a: PyObject, b: float): PyObject = operator.add(a, b)
proc `+`(a: PyObject, b: int): PyObject = operator.add(a, b)

echo(np.array([1,2,3]) + 20.0)
echo(np.array([1,2,3]) + 5)

We would have to do all combinations of operators + types + swapping a and b, maybe this could be automated via e.g. a jinja2 template. They also did this in the PythonKit library for Swift here.

[DylanModesitt]

You can get some of the way there with just making the operator generic in A and B

proc `+`[A, B](a: A, b: B): PyObject =
    callObject(getAttr(operator, "add"), a, b)


proc `*`[A, B](a: A, b: B): PyObject =
    callObject(getAttr(operator, "mul"), a, b)


echo(np.array([1,2,3]) + 20.0)
echo(20.0 + np.array([1,2,3]))