The most efficient one here

@JefeThePug: if you post code, better to fork the kumite.

What's the point of a rust implementation returning a btreemap?

eval is unsafe, avoid using it

really cool kata!

Fair enough reasoning, I suppose.

If its software running locally, its fine. I would not reccomend this for networked applications.

can python translation be pushed / approved?

This is a bad idea - what if someone did something like this: Calculator("+ 0;", "0 ", "print('Thanks eval')")? It may be shorter but you have just opened up this simple program to vulnerabilities.

yeah, I saw it, eval based solution is kinda first that comes to mind and considers vulnerable, I'd like to show another options

Glad you like my solution, Ive made an improved version below, that uses eval. So it's less code and makes more operators available.

right, reduce can be rid of.

nice!

awesome