* bug#32284: special form documentation
@ 2018-07-26 22:44 Nicholas Drozd
2018-07-27 0:04 ` Brett Gilio
0 siblings, 1 reply; 3+ messages in thread
From: Nicholas Drozd @ 2018-07-26 22:44 UTC (permalink / raw)
To: 32284
[-- Attachment #1: Type: text/plain, Size: 899 bytes --]
The Elisp manual section on Special Forms (10.2.7) lists around two dozen
special forms, but two of them aren't special forms.
* `lambda', it turns out, is not a special form, but a macro that wraps
itself in a call to the special form `function'. (The documentation for
`lambda' refers to it as "self-quoting"; this might be better changed to
"self-evaluating".)
* `track-mouse' isn't a special form, but a macro wrapper around the
primitive function `internal--track-mouse', which isn't a special form
either. (Section 29.15 on Mouse Tracking also inaccruately refers to
`track-mouse' as a special form.)
On the other hand, the special form `inline' is not listed in the Special
Forms section.
A list of all special forms can be gotten with
(let (special-forms)
(mapatoms
(lambda (sym)
(when (special-form-p sym)
(push sym special-forms))))
(sort special-forms #'string<))
[-- Attachment #2: Type: text/html, Size: 1195 bytes --]
^ permalink raw reply [flat|nested] 3+ messages in thread
* bug#32284: special form documentation
2018-07-26 22:44 bug#32284: special form documentation Nicholas Drozd
@ 2018-07-27 0:04 ` Brett Gilio
2018-07-28 7:26 ` Eli Zaretskii
0 siblings, 1 reply; 3+ messages in thread
From: Brett Gilio @ 2018-07-27 0:04 UTC (permalink / raw)
To: Nicholas Drozd; +Cc: 32284
Nicholas Drozd writes:
> The Elisp manual section on Special Forms (10.2.7) lists around
> two dozen
> special forms, but two of them aren't special forms.
>
> * `lambda', it turns out, is not a special form, but a macro
> that wraps
> itself in a call to the special form `function'. (The
> documentation for
> `lambda' refers to it as "self-quoting"; this might be better
> changed to
> "self-evaluating".)
>
> * `track-mouse' isn't a special form, but a macro wrapper around
> the
> primitive function `internal--track-mouse', which isn't a
> special form
> either. (Section 29.15 on Mouse Tracking also inaccruately
> refers to
> `track-mouse' as a special form.)
>
> On the other hand, the special form `inline' is not listed in
> the Special
> Forms section.
>
> A list of all special forms can be gotten with
>
> (let (special-forms)
> (mapatoms
> (lambda (sym)
> (when (special-form-p sym)
> (push sym special-forms))))
> (sort special-forms #'string<))
Hi Nicholas,
Thank you for the note. As far as I can see you are correct about
the
method of implementation being macros. But that does not exclude
them
from being special forms, as from my knowledge a special form is
simply
an expression that does not follow the formal rules for the
implementation of a function.
Most lisps define their special forms from a small subset of
primitives
such as lambda and macros, of which these apply.
Anybody else have any input?
--
Brett M. Gilio
Free Software Foundation, Member
https://parabola.nu | https://emacs.org
^ permalink raw reply [flat|nested] 3+ messages in thread
* bug#32284: special form documentation
2018-07-27 0:04 ` Brett Gilio
@ 2018-07-28 7:26 ` Eli Zaretskii
0 siblings, 0 replies; 3+ messages in thread
From: Eli Zaretskii @ 2018-07-28 7:26 UTC (permalink / raw)
To: Brett Gilio; +Cc: 32284-done, nicholasdrozd
> From: Brett Gilio <brettg@posteo.net>
> Date: Thu, 26 Jul 2018 19:04:32 -0500
> Cc: 32284@debbugs.gnu.org
>
> Anybody else have any input?
I do: the point about track-mouse is correct: it used to be a special
form (implemented in C), but nowadays is a macro. So I removed it
from the list of special forms.
I didn't do anything about 'lambda', because its user-facing behavior
is that of a special form, and the fact that it is a thin wrapper
around 'function' is an implementation detail that doesn't necessarily
matter in this context.
With that, I'm closing this bug report.
Thanks.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2018-07-28 7:26 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-07-26 22:44 bug#32284: special form documentation Nicholas Drozd
2018-07-27 0:04 ` Brett Gilio
2018-07-28 7:26 ` Eli Zaretskii
Code repositories for project(s) associated with this external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.