Re: how to highlight block end in Python-mode indentation

[Yuri Khan]

On Sun, May 21, 2017 at 6:38 PM, Krishnakant <krmane@openmailbox.org> wrote:

> The base is large enough, more than 1500 lines in a buffer (python module ).

That is a lot. See if any top-level functions or classes want to live
in separate modules.

> There is a lot of nesting going on and we all know that we do get lost in
> it.
> Do you have some solution?

Apply Torvalds’ razor: “if you need more than 3 levels of indentation,
you’re screwed[…], and should fix your program”.

See which deep-nested blocks carry out some action that could be given
a name. Extract those as functions. If you see a block of code with an
explanatory comment before it — that’s a function wanting to break
out.

Also, The Zen of Python, item 5: “Flat is better than nested.”

See if you have this pattern:

def …:
    if some condition:
        do something
        …

Rewrite this to:

def …:
    if not some condition:
        return
    do something
    …

Similarly with loops, using “continue”.

Sometimes replacing conditions with conditional expressions (x if y
else z) and loops with comprehensions and utility functions will do
wonders to your nesting levels.

> Basically I have now figured out that spaces instead of tabs makes elpy work
> fine with highlight-indentation-mode.  So our team will have to switch to
> using spaces again.

You use tabs with Python in a *team*?

Print out PEP8. Discuss it with your team. Unless you have good
reasons, format according to that. (Unfortunately, having lots of
existing code qualifies as “good reasons”.)