I like this. Something that I would use for sure. I have used a lot of:
``` (value: None | object ) or default ``` , but I stopped for obvious reasons. However, I miss those days, when I was ignorant that this is not a good idea. > On 11 Jul 2023, at 01:17, David Mertz, Ph.D. <david.me...@gmail.com> wrote: > > This is basically PEP 505 – None-aware operators > (https://peps.python.org/pep-0505/ <https://peps.python.org/pep-0505/>). > > I've generally been opposed to that, but clearly some serious and smart > Pythonistas have supported it. That PEP is a bigger lift than your > suggestion, but correspondingly more general. > > On Mon, Jul 10, 2023, 6:04 PM Jothir Adithyan <adithyanjot...@gmail.com > <mailto:adithyanjot...@gmail.com>> wrote: > Hi everyone, > > I would like to briefly present my idea regarding the `get` function commonly > used with dictionaries. When working with large amounts of JSON data, I often > encounter code that doesn't feel very Pythonic to me. > > Problem Statement: > > The `get` function allows chaining of method calls, which is quite useful > when working with dictionaries. It also has a convenient `default` parameter > that returns a default value if the key is not found in the dictionary. This > feature makes it safe and easy to use. However, problems arise when the > dictionary contains the key we are accessing, but the corresponding value is > `None`. In such cases, subsequent `get` calls fail because the `get` method > belongs to objects of type `dict` and not `None`. To address this, I propose > adding a new parameter to the `get` function or introducing a new function > called `get_or` that swiftly handles this issue. This new parameter, called > `arbitrary`, would accept an arbitrary value to be returned by subsequent > `get` calls in case the retrieved value of the key is `None`. > > Assumptions: > > The problem statement is based on a few assumptions: > - You prefer chaining `get` statements for cleaner code. > - You expect at least some of the `get` methods to return `None`. > - You want to avoid the hassle of using `try` and `except` for every `get` > chain. > > If you fall into the category of people who wish for a simpler way to work > with dictionaries and handle large amounts of data, I hope you can empathise > with this proposal. > > I have made a simple implementation by modifying the `get` method, which is > below this thread. I would appreciate your valuable input on this feature. > Before diving into coding, I want to make sure this is not a bad idea waiting > to reveal itself in the dark. > > Thank you for taking the time to read this thread. Your feedback is greatly > appreciated. > > Best regards, > Jothir Adithyan > > > > > **Runnable Version** > https://replit.com/@Adithyan71/GetOr <https://replit.com/@Adithyan71/GetOr> > > > > **Code Samples.** > > ``` > class PlayDict(dict): > def get_or(self, key, arbitrary=None, default=None): > if not self.__contains__( > key > ): # case 1 the key does not exist hence the default value > return default > elif ( > self[key] is None > ): # case 2 key does exist but the value is None return the arb > value > return arbitrary > return self[key] # case 3 the key is present and the value is not > None > > > import contextlib > parent_dict = PlayDict() > parent_dict['k1'] = None > parent_dict['k2'] = {"child_key": "val"} # Parent dict can contain nested > dicts > > with contextlib.suppress(AttributeError): > result = parent_dict.get("k1", {}).get("child_key") # This will raise > AttributeError > > result = parent_dict.get_or("k1", default={}, arbitrary={}).get("child_key") > # This will work > > print(result) > ``` > _______________________________________________ > Python-ideas mailing list -- python-ideas@python.org > <mailto:python-ideas@python.org> > To unsubscribe send an email to python-ideas-le...@python.org > <mailto:python-ideas-le...@python.org> > https://mail.python.org/mailman3/lists/python-ideas.python.org/ > <https://mail.python.org/mailman3/lists/python-ideas.python.org/> > Message archived at > https://mail.python.org/archives/list/python-ideas@python.org/message/IELDCURRVQXCPGD4EPPLL7MYWJT4XHKV/ > > <https://mail.python.org/archives/list/python-ideas@python.org/message/IELDCURRVQXCPGD4EPPLL7MYWJT4XHKV/> > Code of Conduct: http://python.org/psf/codeofconduct/ > <http://python.org/psf/codeofconduct/> > _______________________________________________ > Python-ideas mailing list -- python-ideas@python.org > To unsubscribe send an email to python-ideas-le...@python.org > https://mail.python.org/mailman3/lists/python-ideas.python.org/ > Message archived at > https://mail.python.org/archives/list/python-ideas@python.org/message/4BCGPZ6TJFN4DCXIPR5I24ND7MOYPV5T/ > Code of Conduct: http://python.org/psf/codeofconduct/
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