https://github.com/takluyver/backcall

Backwards compatible callback APIs
https://github.com/takluyver/backcall

Last synced: about 2 months ago
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Backwards compatible callback APIs

• Host: GitHub
• URL: https://github.com/takluyver/backcall
• Owner: takluyver
• License: bsd-3-clause
• Created: 2014-01-17T23:40:51.000Z (almost 11 years ago)
• Default Branch: master
• Last Pushed: 2020-06-09T15:11:46.000Z (over 4 years ago)
• Last Synced: 2024-06-11T17:35:43.313Z (7 months ago)
• Language: Python
• Homepage:
• Size: 25.4 KB
• Stars: 17
• Watchers: 6
• Forks: 10
• Open Issues: 0
• Metadata Files:
  • Readme: README.rst
  • License: LICENSE

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README

        
========

backcall

========

.. image:: https://travis-ci.org/takluyver/backcall.png?branch=master

        :target: https://travis-ci.org/takluyver/backcall

Specifications for callback functions passed in to an API

If your code lets other people supply callback functions, it's important to

specify the function signature you expect, and check that functions support that.

Adding extra parameters later would break other peoples code unless you're careful.

backcall provides a way of specifying the callback signature using a prototype

function::

    from backcall import callback_prototype

    

    @callback_prototype

    def handle_ping(sender, delay=None):

        # Specify positional parameters without a default, and keyword

        # parameters with a default.

        pass

    

    def register_ping_handler(callback):

        # This checks and adapts the function passed in:

        callback = handle_ping.adapt(callback)

        ping_callbacks.append(callback)

If the callback takes fewer parameters than your prototype, *backcall* will wrap

it in a function that discards the extra arguments. If the callback expects

more arguments, a TypeError is thrown when it is registered.

For more details, see the `docs `_ or

the `Demo notebook `_.

The tests are run with `pytest `_. In the root directory,

execute::

    py.test