Here is a simple implementation of that Sentinel class: https://github.com/fluentpython/example-code-2e/blob/master/25-class-metaprog/sentinel/sentinel.py
Tests in the same directory. That's not a real package yet, just a couple of super simple examples I may use in Fluent Python 2e. Cheers, Luciano On Sun, May 23, 2021 at 9:37 PM Luciano Ramalho <luci...@ramalho.org> wrote: > > Sorry about my detour into the rejected idea of a factory function. > > But how about this class-based API? > > class NotGiven(Sentinel): > pass > > > Now I can use NotGiven as the sentinel, and its default repr is <NotGiven>. > > Behind the scenes we can have a SentinelMeta metaclass with all the > magic that could be required--including the default __repr__ method. > > Cheers, > > Luciano > > > > > > > > > (Note: This link will break once the temporary branch is deleted.) > > > > > > I wrote it to summarize the discussions, organize my thoughts and > > > explore the options. I stopped working on it late at night and sent a > > > link to a few people to get some opinions. I didn’t intend to make it > > > public yet, but it was noticed and replied to on the > > > discuss.python.org thread where I put up the poll [1], so the cat is > > > out of the proverbial bag now… > > > > > > Luciano, your wish is granted! ;) > > > - Tal Einat > > > > > > [1] https://discuss.python.org/t/sentinel-values-in-the-stdlib/8810/ > > > > > > > > -- > > Luciano Ramalho > > | Author of Fluent Python (O'Reilly, 2015) > > | http://shop.oreilly.com/product/0636920032519.do > > | Technical Principal at ThoughtWorks > > | Twitter: @ramalhoorg > > > > -- > Luciano Ramalho > | Author of Fluent Python (O'Reilly, 2015) > | http://shop.oreilly.com/product/0636920032519.do > | Technical Principal at ThoughtWorks > | Twitter: @ramalhoorg -- Luciano Ramalho | Author of Fluent Python (O'Reilly, 2015) | http://shop.oreilly.com/product/0636920032519.do | Technical Principal at ThoughtWorks | Twitter: @ramalhoorg _______________________________________________ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-le...@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/DAUQOKAJG7FZYY24JBG7ZIGA3TFZA4OY/ Code of Conduct: http://python.org/psf/codeofconduct/
