Spice up your code with wrappers! In Python, a wrapper, also known as a decorator, is simply encapsulating a function within other functions.
| 1 2 3 4 5 6 7 | @wrapper def my_func(a, b=2): print(b) @meta_decorator(foo="bar") def my_other_func(**kwargs): print(kwargs) |
In Reusables, all the wrappers take arguments, aka meta decorators, so you will at minimum have to end them with parens ()s. Let’s take a look at the one I use … [Read more…]
Often times in python there comes a need to have multiple functions act in a similar manner. It could be anything from making sure that similar functions output the right type of result, they all log when they are called or all report exceptions in the same way. An easy and repeatable way to accomplish … [Read more…]
Reusables 0.8 has just been released, and it’s about time I give it a proper introduction. I started this project three years ago, with a simple goal of keeping code that I inevitably end up reusing grouped into a single library. It’s for the stuff that’s too small to do well as it’s own library, … [Read more…]
Exceptions in Python aren’t new, and pretty easy to wrap your head around. Which means you should have no trouble following what this example will output.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 | import warnings def bad_func(): try: assert False and True or False except AssertionError as outer_err: try: assert None is False except AssertionError as inner_err: warnings.warn("None is not False", UserWarning) raise inner_err from None else: return None else: return True finally: return False print(bad_func()) |
Simple, right? It raises both except clauses, triggering the warning and so your screen will obviously print False and the warning.
| 1 2 3 | False C:/python_file.py:15: UserWarning: None is not False warnings.warn("None is not False", UserWarning) |
So if you followed that without issue and … [Read more…]
Every coder will come across the same aggravating issue one day, finding a script or library you think you need, and it has zero instructions. Or the examples don’t work, or there is so much writing and so little substance you can’t hope to dig through it all to discover how it’s meant to be … [Read more…]
Logging vs Print The difference between logging and using print isn’t simply personal preference, rather choosing the proper tool per use case. Check out the Python docs when to use logging if you don’t believe me. If you are simply using Python to write scripts with clear paths and failure on error, it’s perfectly reasonable to not have … [Read more…]