Handy function decorator for completion notification in e.g. Jupyter Notebooks

notify_deco.py

# A nestable function-completion notification decorator
# File: notify_deco.py
# Author: Jonathan David Page <jonathan@sleepingcyb.org>
#
# This is free and unencumbered software released into the public domain.
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# distribute this software, either in source code form or as a compiled
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# of this software dedicate any and all copyright interest in the
# software to the public domain. We make this dedication for the benefit
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# software under copyright law.
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import functools


class CompletionNotifier:
    def __init__(self, notify_fun):
        self.notify_fun = notify_fun
        self.isinner = False

    def __call__(self, f):
        @functools.wraps(f)
        def wrapper(*args, **kwargs):
            isinner = self.isinner
            self.isinner = True
            try:
                return f(*args, **kwargs)
            finally:
                self.isinner = isinner
                if not self.isinner:
                    self.notify_fun(f)

        return wrapper


def my_notify(*args):
    print("Done!")


notify_on_complete = CompletionNotifier(my_notify)


@notify_on_complete
def foo():
    print("Foo!")


@notify_on_complete
def bar():
    print("Bar 1")
    foo()
    print("Bar 2")