I often have code of the form:
def my_fun(): allocate_res1() try: # do stuff allocate_res2() try: # do stuff allocate_res3() try: # do stuff finally: cleanup_res3() finally: cleanup_res2() finally: cleanup_res1()
With increasing number of managed resources, the indentation becomes really annoying, there is lots of line noise, and I don't like the fact that the cleanup is so far away from the allocation.
I would much rather have something like this:
def my_fun(): allocate_res1() atreturn.register(cleanup_res1) # do stuff allocate_res2() atreturn.register(cleanup_res2) # do stuff allocate_res3() atreturn.register(cleanup_res3) # do stuff return
Has the idea of implementing such "on return" handlers ever come up? Maybe there is some tricky way to do this with function decorators?