Paul Ganssle <p.gans...@gmail.com> added the comment:

> In fact, you're proposing to use exit as a keyword, but lying about it to the 
> users. If it were really so important, then it _should_ be a keyword, and at 
> least I'd know that I can't use it for my variables anymore. (It's not the 
> first time such a thing would happen. The same thing happened with `async` a 
> few years ago.) But please don't introduce those "keywords just in a 
> particular context", they are horrible from the perspective of usability.

We already have so-called "soft keywords", e.g. `match`, so the horse is out of 
the barn at this point.

I'm not sure why this is closed as rejected — I don't see any decision one way 
or the other in this thread or on the PR, did I miss it?

I am struggling to understand how this is a user-hostile change; it is not 
unreasonable for a REPL to have some commands for interacting with the REPL 
which are not Python functions. I have accidentally typed `exit` instead of 
`exit()` many times, and one of the reasons I and many others like IPython is 
that `exit` exits the REPL. It has never once caused a problem for me, as far 
as I can tell. I cannot imagine that it is a common scenario for someone to 
type "exit" in order to inspect the "exit" object — it doesn't even have a 
useful repr!

The only reason you'd do this would be if you knew what it does and were 
demonstrating it, or if you were exploring what the various builtins are (which 
I think is very rare, and you'd probably only have to learn that lesson once).

Vedran's point, however, that you could do `exit = some_func()` and then type 
`exit` to try and inspect the `exit` object is a solid one. That said, I think 
we can get around this fairly easily (albeit with the cost of some additional 
complexity in the "handle the exit keyword" function) — if there's a single AST 
node that is a name and the name is "exit" or "quit", the REPL inspects locals 
and globals to see if the object referred to is a Quitter, and if so it exits, 
otherwise pass through the command as normal (possibly raising a warning like, 
"Did you mean to exit? You have shadowed the `exit` builtin, so use 
Ctrl-Z/Ctrl-D to exit or delete your `exit` object and try again").

I understand the arguments for purity and explicability and I'm often one of 
the first people to argue for keeping things consistent and understandable, but 
this is one of those things where we could significantly improve user 
experience for no practical cost. We can identify with very high certainty the 
situations in which a user intended to exit the REPL, we should go ahead and do 
it to provide a more intuitive REPL experience.

----------

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<https://bugs.python.org/issue44603>
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