This feels superfluous. Instead of creating new dict class I would propose
either:
1. Not to have None values
a) It is most likely possible to pre-delete all None values before you use
the dict = {k: v for k, v in dict if v is not None}
b) Not to create them in the first place (if it depends on you)
2. Or simply: (dict.get(‘k1’) or dict()).get(‘child_key')
> On 10 Jul 2023, at 22:18, Jothir Adithyan <[email protected]> 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
>
>
>
> **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)
> ```
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