How to handle “duck typing” in Python?

Question

I usually want to keep my code as generic as possible. I\'m currently writing a simple library and being able to use different types with my library feels extra important th

Answer 1

If you just want the unimplemented methods to do nothing, you can try something like this, rather than the multi-line try/except construction:

getattr(obj, "sleep", lambda: None)()

However, this isn't necessarily obvious as a function call, so maybe:

hasattr(obj, "sleep") and obj.sleep()

or if you want to be a little more sure before calling something that it can in fact be called:

hasattr(obj, "sleep") and callable(obj.sleep) and obj.sleep()

This "look-before-you-leap" pattern is generally not the preferred way to do it in Python, but it is perfectly readable and fits on a single line.

Another option of course is to abstract the try/except into a separate function.