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 **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 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/IELDCURRVQXCPGD4EPPLL7MYWJT4XHKV/ Code of Conduct: http://python.org/psf/codeofconduct/
