[Python-Dev] Re: The python command help is too long

On Sat, Dec 18, 2021 at 4:00 PM Guido van Rossum wrote:

On Sat, Dec 18, 2021 at 2:16 PM Serhiy Storchaka wrote:

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The output of "python -h" is 104 lines long now. It was only 51 lines in 3.6. 35% of it is about the -X option, and 30% about environment variables. Also some lines in the -X option description are too long (102 columns). Both topics are "advanced" and mostly interested for debugging. I suggest to move them out of the main help output.

Sounds like a good plan.

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The are two options:

1. Move it to pydoc topics. The advantage is that it is a standard way, there are already 88 topics. The disadvantage is that this information will be not available in "minimal" installations of Python which do not include docs.

2. Add command-line options like -hX and -henv. The information will always be available with the interpreter, but the interface is special.

For -X, I suggest we could output the following line:

-X opt : implementation-specific option; use -X help to list options.

+1 from me.

We could also see if we can put the help text for each of the supported -X flags in the table defining these flags (sorry, I can't recall where it lives, but I'm pretty sure I've seen such a table.)

For env vars I think moving this to pydoc is fine; I don't think we have a process or mechanism that ensures the docs for env vars are even complete. (We don't have one for the flags either, but somehow I find it hard to conceive of someone adding a new command line flag without them or someone else involved in the code review thinking of updating the help text. But I find it quite conceivable that someone adds a new env var used only in a corner case without anyone thinking to update the docs. And I presume that the -E flag isn't honored 100% of the time either.)

But I wouldn't object to a -h sub-option that lists environment vars either.

I think an option to `-h` for environment variables is also good as that command can be the generic `-h` output as well without resorting to needing to run Python code like pydoc to get at more help.