Indentation of cond forms in (Emacs) Lisp mode

Indentation of cond forms in (Emacs) Lisp mode

[Bozhidar Batsov]

I noticed that `cond' forms in Emacs Lisp mode and Lisp mode are 
indented with just one space, unlike most other "control" structures:

(cond
  ((x) (y))
  (t (z))

Why is that? Seems odd to treat the differently from the likes of `when' 
for instance:

(when something
   (do-something))

I'm asking because this leaked into clojure-mode as well and we're now 
discussing whether it's a bug or something reasonable.

Cheers,
Bozhidar

Re: Indentation of cond forms in (Emacs) Lisp mode

[Andreas Schwab]

"Bozhidar Batsov" <bozhidar.batsov@gmail.com> writes:

> I noticed that `cond' forms in Emacs Lisp mode and Lisp mode are indented
> with just one space, unlike most other "control" structures:
>
> (cond
>  ((x) (y))
>  (t (z))
>
> Why is that?

The intention is that you do not break after cond, so it isn't treated
specially, ie. like a normal function call.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."

Re: Indentation of cond forms in (Emacs) Lisp mode

[Bozhidar Batsov]

On 3 Jun 2014, at 17:22, Andreas Schwab wrote:

> "Bozhidar Batsov" <bozhidar.batsov@gmail.com> writes:
>
>> I noticed that `cond' forms in Emacs Lisp mode and Lisp mode are 
>> indented
>> with just one space, unlike most other "control" structures:
>>
>> (cond
>> ((x) (y))
>> (t (z))
>>
>> Why is that?
>
> The intention is that you do not break after cond, so it isn't treated
> specially, ie. like a normal function call.
>
> Andreas.

Still, it seems a bit arbitrary. Are there are constructs treated in the 
same manner?

Also, how is this any different from a macro like `with-temp-buffer`, 
which has regular indentation (2 spaces)?

(with-temp-buffer
   (do-something)
   (do-something-else))

>
> -- 
> Andreas Schwab, SUSE Labs, schwab@suse.de
> GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA 
> B9D7
> "And now for something completely different."

Re: Indentation of cond forms in (Emacs) Lisp mode

[Andreas Schwab]

"Bozhidar Batsov" <bozhidar.batsov@gmail.com> writes:

> Also, how is this any different from a macro like `with-temp-buffer`,
> which has regular indentation (2 spaces)?

This matches the generic pattern of (with-foo [sexp] [body]...), which
is intented to be broken before [body].

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."

Re: Indentation of cond forms in (Emacs) Lisp mode

[Stefan Monnier]

>> The intention is that you do not break after cond, so it isn't treated
>> specially, ie. like a normal function call.
> Still, it seems a bit arbitrary.

Yes.  I don't think you'll find a much better answer.


        Stefan