[gruez]

> It should print the first to stdout and the second to stderr. That's completely consistent with how stdout and stderr are usually used.

That makes sense from a unix tool perspective, but not from a python repl perspective. The repl's behavior is to print the result from the last executed statement. For the exit function, the __repr__ method was overwriten to print the message. That way when you type in "exit", the last value would be exit (the function), and the overwritten __repr__ method causes the help message to be printed. There's no way to have it print to both without adding in some repl specific hacks.

    >>> exit
    Use exit() or Ctrl-Z plus Return to exit
    >>> exit.__repr__()
    'Use exit() or Ctrl-Z plus Return to exit'

[dmurray]

How about

    def __repr__(self):
        import warnings
        warnings.warn("Use exit() or Ctrl-Z plus Return to exit")
        return super().repr()

[edflsafoiewq]

What if you aren't in the REPL? Using __repr__ at all seems like an abstraction violation. It should be the REPL's job to layer on special casing for exit.

[amluto]

The actual behavior is indeed a bit ridiculous:

    >>> print('%r' % str)
    <class 'str'>
    >>> def whatisit(x):
    ...     print('It is %r' % x)
    ... 
    >>> whatisit(min)
    It is <built-in function min>
    >>> whatisit(exit)
    It is Use exit() or Ctrl-D (i.e. EOF) to exit

Excuse me?

IMO if the REPL wanted a friendly feature like this, it should be a generic REPL feature, not a hack applied to the function exit.

[dale_glass]

Also a bit funny:

    >>> def get_function():
    ...     return exit
    ... 
    >>> a = get_function()
    >>> a
    Use exit() or Ctrl-D (i.e. EOF) to exit

[dmurray]

You could use the same pattern as DeprecationWarning. It's suppressed by default and test runners like pytest enable it. A new ReplWarning could be enabled by interactive tools only.

I think I agree though: what you really want to special case is the situation where the user types precisely 'exit<cr>' at a REPL prompt, and that hack needs to exist further up the stack than in the implementation of __repr__.

[hiccuphippo]

Thanks for this, it never occurred to me it used __repr__ for the message. I just added this to my .pythonrc

    exit.__class__.__repr__ = lambda _: exit()
    quit = exit

Edit, you also need this in your bashrc:

    export PYTHONSTARTUP=~/.pythonrc