Re: Org Babel says 1 + 1 in Python is None

[Jack Kamm <jackkamm@gmail.com>]

Ihor Radchenko <yantar92@posteo.net> writes:

> I'm afraid that trying to replicate Python REPL behavior for
> non-interactive src blocks will be beyond what we can reasonably do in
> Org: we would somehow need to detect the last statement in the src
> blocks, which may or may not span a single line; and multiline statements
> will need to use some kind of Python parser. All this sounds way too
> fragile to be practical.

Well, ob-python sessions implement this sort of parser in
`org-babel-python-format-session-value', which AFAIK is robust.

I think it would be feasible to switch non-session blocks to use this
parser, which IMO is nicer behavior -- the "return" statements always
felt weird to me.

But a major reason not to do it is to avoid breaking compatibility. Lots
of old ob-python nonsession blocks with "return" statements out there.

But perhaps we could implement an option to switch nonsession value to
the session value behavior (omitting "return"). The default behavior
should remain unchanged (requiring "return"), but in the long term we
could consider changing the default if there is consensus for it.

(I likely don't have bandwidth to implement such an option in the near
term, but would be supportive if anyone wants to have a go at it).