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What I would love to see in a future version of python is being able to do `user["email"]` or `user.email` independently of the reason. Sometimes both work, som

What I would love to see in a future version of python is being able to do `user["email"]` or `user.email` independently of the reason. Sometimes both work, sometimes only one of the two and an error in throw for the other one. I don't care why, I just want it to work, it's such a basic feature. Something even crazier would be to have an equivalent of `console.log` in python. It would be an amazing feature but I think I'm the only one wanting it. I know I can use `print` or different logger. But it's a lot more complicated to use and the output is a lot less navigable than in javascript. PHP also has `var_dump`. But we don't have any equivalent in python.

masklinn 3y ago
> What I would love to see in a future version of python is being able to do `user["email"]` or `user.email` independently of the reason. Sometimes both work, sometimes only one of the two and an error in throw for the other one. I don't care why, I just want it to work, it's such a basic feature. It's an absolutely terrible idea and I'm thankful that there's so little chance it'll ever happen. I don't want random objects to become mappings, nor do I want mapping entries and their attributes to conflict. Javascript is a bad language and this is one of its worst features. > Something even crazier would be to have an equivalent of `console.log` in python. It would be an amazing feature but I think I'm the only one wanting it. I know I can use `print` or different logger. But it's a lot more complicated to use and the output is a lot less navigable than in javascript. You... can just call `logging.whatever()`, after having called `logging.basicConfig()` to set up your basic config? I fail to see how that would change anything to navigability. `console.log` is not inherently navigable, it's the browser's console UI which provides some navigability.
__s 3y ago
https://docs.python.org/3/library/functions.html#dir https://docs.python.org/3/library/functions.html#dir
jwkane 3y ago
If you want to write javascript, use javascript. There are ways to get what you're asking for depending on your use case. types.SimpleNamespace in the standard library provides one approach. "There should be one-- and preferably only one --obvious way to do it." (zen of python) I do agree that python logging is a weak point. It is too easy to do it wrong -- particularly when you are a few modules deep.
- BoumTAC 3y ago
  I really like Python and I love using it. But I think some improvements could be done on such "basic feature". > "There should be one-- and preferably only one --obvious way to do it." (zen of python) Look at all the other possibilities to do `f"hello {name}`. That are more than one obvious way to do it.
gnulinux 3y ago
In terms of programming language construction making `x.y` and `x["y"]` equivalent looks appealing and, admittedly, cute but there are some problems: * For new languages: It's not generic enough since there is no equivalent of `x[t]` if t is of a non-string type. E.g. there is no way to express `x[(1,2,3)]` or `x[3]` or `x[frozenset({1, 2, "foo"})]` this way. * For existing languages like Python: this would be a breaking change since things that can do `x.y` and `x[t]` are structurally different in Python so they're typed differently. One are called "mappings" and the other are "objects", they're completely different things. Hence, you'll get cases where `x["foo"] == 5` but `x.foo == 4` so this will for sure break some programs. Too much pain for no gain.
- BoumTAC 3y ago
  Don't you think `x["foo"] == 5` but `x.foo == 4` is a hell of a lot confusing ? Don't you think it should not be possible to have such a thing ? To me it's so prone to error and there is absolutely too much gain to fix this.
  - pedvide 3y ago
    In pandas for example that can happen often: `df["count"] == 5` and `df.count == 5` are logically different expressions that will give different answers
  - execveat 3y ago
    No, there is no confusion here at all (for a Python developer). I would consider it a code smell though as the whole problem is completely avoidable by better naming. By the way, there is a vulnerability (Prototype Pollution) that is only possible due to this behaviour in JS: https://portswigger.net/web-security/prototype-pollution https://portswigger.net/web-security/prototype-pollution
  - lozenge 3y ago
    So how can d.update() coexist with d["update"]? Updating a dictionary vs examining a dictionary that has a key "update"?
  - 3y ago
WorldMaker 3y ago
I think what you are looking for as an equivalent to the JS `console.log`/PHP `var_dump` feature set is available in f-string formats. There's not one perfect format to rule them all but the "=" "self-documenting" debug format such as `f"{some_obj=}"` probably gives you a good starting point for what you are looking for most of the time. Sometimes you still want the `str()` or `repr()` representation specifically and would want something like `f"{some_obj=!s}"` or `f"{some_obj=!r}"` respectively. In some cases objects you want pretty-printed to a console might have custom `__format__()` representations as well and it might be something like `f"{some_obj=:some-custom-format}"`. It's obviously all still differently useful than JS having a full object browser embedded in most common consoles today, but there is interesting power to explore in f-string formats if you need quick and dirty logs of object states. https://docs.python.org/3/whatsnew/3.8.html#bpo-36817-whatsnew https://docs.python.org/3/whatsnew/3.8.html#bpo-36817-whatsn...
ketzu 3y ago
> PHP also has `var_dump`. But we don't have any equivalent in python. Maybe pprint is for you: from pprint import pprint # usage, but can do more as well and has more config stuff if needed pprint({'a':'b'}) https://docs.python.org/3/library/pprint.html
- masklinn 3y ago
  `vars` as well: https://docs.python.org/3/library/functions.html#vars https://docs.python.org/3/library/functions.html#vars Although it'd be nice if it worked with slotted classes instead of just blowing up. Dataclasses have asdict which work on both, but it's annoying there's nothing for regular classes.
simonw 3y ago
There are a bunch of options for getting user["email"] and user.email to do the same thing: 1. Write a class with custom __getitem__ and __getattr__ methods 2. Use a template system like Django or Jinja that implements this in certain situations 3. Use a library like https://pypi.org/project/python-box/ https://pypi.org/project/python-box/
fwungy 3y ago
A dict_to_object function would be a good little intermediate exercise.

masklinn 3y ago

> What I would love to see in a future version of python is being able to do `user["email"]` or `user.email` independently of the reason. Sometimes both work, sometimes only one of the two and an error in throw for the other one. I don't care why, I just want it to work, it's such a basic feature. It's an absolutely terrible idea and I'm thankful that there's so little chance it'll ever happen. I don't want random objects to become mappings, nor do I want mapping entries and their attributes to conflict. Javascript is a bad language and this is one of its worst features. > Something even crazier would be to have an equivalent of `console.log` in python. It would be an amazing feature but I think I'm the only one wanting it. I know I can use `print` or different logger. But it's a lot more complicated to use and the output is a lot less navigable than in javascript. You... can just call `logging.whatever()`, after having called `logging.basicConfig()` to set up your basic config? I fail to see how that would change anything to navigability. `console.log` is not inherently navigable, it's the browser's console UI which provides some navigability.

__s 3y ago

https://docs.python.org/3/library/functions.html#dir https://docs.python.org/3/library/functions.html#dir

jwkane 3y ago

If you want to write javascript, use javascript. There are ways to get what you're asking for depending on your use case. types.SimpleNamespace in the standard library provides one approach. "There should be one-- and preferably only one --obvious way to do it." (zen of python) I do agree that python logging is a weak point. It is too easy to do it wrong -- particularly when you are a few modules deep.

BoumTAC 3y ago
I really like Python and I love using it. But I think some improvements could be done on such "basic feature". > "There should be one-- and preferably only one --obvious way to do it." (zen of python) Look at all the other possibilities to do `f"hello {name}`. That are more than one obvious way to do it.

gnulinux 3y ago

In terms of programming language construction making `x.y` and `x["y"]` equivalent looks appealing and, admittedly, cute but there are some problems: * For new languages: It's not generic enough since there is no equivalent of `x[t]` if t is of a non-string type. E.g. there is no way to express `x[(1,2,3)]` or `x[3]` or `x[frozenset({1, 2, "foo"})]` this way. * For existing languages like Python: this would be a breaking change since things that can do `x.y` and `x[t]` are structurally different in Python so they're typed differently. One are called "mappings" and the other are "objects", they're completely different things. Hence, you'll get cases where `x["foo"] == 5` but `x.foo == 4` so this will for sure break some programs. Too much pain for no gain.

BoumTAC 3y ago
Don't you think `x["foo"] == 5` but `x.foo == 4` is a hell of a lot confusing ? Don't you think it should not be possible to have such a thing ? To me it's so prone to error and there is absolutely too much gain to fix this.
- pedvide 3y ago
  In pandas for example that can happen often: `df["count"] == 5` and `df.count == 5` are logically different expressions that will give different answers
- execveat 3y ago
  No, there is no confusion here at all (for a Python developer). I would consider it a code smell though as the whole problem is completely avoidable by better naming. By the way, there is a vulnerability (Prototype Pollution) that is only possible due to this behaviour in JS: https://portswigger.net/web-security/prototype-pollution https://portswigger.net/web-security/prototype-pollution
- lozenge 3y ago
  So how can d.update() coexist with d["update"]? Updating a dictionary vs examining a dictionary that has a key "update"?
- 3y ago

WorldMaker 3y ago

I think what you are looking for as an equivalent to the JS `console.log`/PHP `var_dump` feature set is available in f-string formats. There's not one perfect format to rule them all but the "=" "self-documenting" debug format such as `f"{some_obj=}"` probably gives you a good starting point for what you are looking for most of the time. Sometimes you still want the `str()` or `repr()` representation specifically and would want something like `f"{some_obj=!s}"` or `f"{some_obj=!r}"` respectively. In some cases objects you want pretty-printed to a console might have custom `__format__()` representations as well and it might be something like `f"{some_obj=:some-custom-format}"`. It's obviously all still differently useful than JS having a full object browser embedded in most common consoles today, but there is interesting power to explore in f-string formats if you need quick and dirty logs of object states. https://docs.python.org/3/whatsnew/3.8.html#bpo-36817-whatsnew https://docs.python.org/3/whatsnew/3.8.html#bpo-36817-whatsn...

ketzu 3y ago

> PHP also has `var_dump`. But we don't have any equivalent in python. Maybe pprint is for you: from pprint import pprint # usage, but can do more as well and has more config stuff if needed pprint({'a':'b'}) https://docs.python.org/3/library/pprint.html

masklinn 3y ago
`vars` as well: https://docs.python.org/3/library/functions.html#vars https://docs.python.org/3/library/functions.html#vars Although it'd be nice if it worked with slotted classes instead of just blowing up. Dataclasses have asdict which work on both, but it's annoying there's nothing for regular classes.

simonw 3y ago

There are a bunch of options for getting user["email"] and user.email to do the same thing: 1. Write a class with custom __getitem__ and __getattr__ methods 2. Use a template system like Django or Jinja that implements this in certain situations 3. Use a library like https://pypi.org/project/python-box/ https://pypi.org/project/python-box/

fwungy 3y ago

A dict_to_object function would be a good little intermediate exercise.