Panyc

Super simple python package to solve 2 problems:

• In Python assert is not guaranteed to work (see the -O flag)
• The very convenient todo()/unreachable()/... functions to panic in case reached, are missing

Usage

from panyc import raise_if

def is_even(x):
	raise_if(type(x) != int, f"expected an integer, got {type(x)}")
	return x % 2 == 0

def main():
	x = 6.9
	print("Is", x, "even?", is_even(x))

main()

Will result in AssertionError: /path/to/file/example.py:4: expected an integer, got <class 'float'>

A couple of notice:

• first of all the condition must be true to raise, in the contrary of assert where it must be false
• secondly it raise an AssertionError as well, so the error handling remain the same

So if you plan to rewrite your asserts you have to change the condition and nothing else

from panyc import todo

def end_world_hungry():
	todo()

def main():
	end_world_hungry()

main()

Will result in NotImplementedError: /path/to/file/example.py:4: Function "end_world_hungry" not implemented

from panyc import unreachable

def sound(x):
	if x == "cat":
		return "meow"
	elif x == "dog":
		return "woof"
	elif x == "duck":
		return "quack"
	unreachable() # we do not expect other animals

def main():
	print(sound("crocodile"))

main()

Will result in NotImplementedError: /path/to/file/example.py:10: Reached unreachable code in "sound"

Installation

Just copy the only file panyc.py in your project.

If you like the slop, there's also the package on pypi:

$ pip install panyc