info reference syntax

info reference syntax

[Dan Davison]

What does this syntax mean? 

,----
| See Info node `(viper)Top'.
`----

Is there some way of using it to immediately access the info node
referred to? Where is it documented?

Thanks!

Dan

-- 
http://www.stats.ox.ac.uk/~davison

Re: info reference syntax

[Lennart Borgman]

On Fri, Jan 9, 2009 at 8:22 PM, Dan Davison <davison@stats.ox.ac.uk> wrote:
> What does this syntax mean?
>
> ,----
> | See Info node `(viper)Top'.
> `----
>
> Is there some way of using it to immediately access the info node
> referred to?

M-: (info "(viper) Top")

Re: info reference syntax

[Dan Davison]

On Fri, Jan 09, 2009 at 08:27:40PM +0100, Lennart Borgman wrote:
> On Fri, Jan 9, 2009 at 8:22 PM, Dan Davison <davison@stats.ox.ac.uk> wrote:
> > What does this syntax mean?
> >
> > ,----
> > | See Info node `(viper)Top'.
> > `----
> >
> > Is there some way of using it to immediately access the info node
> > referred to?
> 
> M-: (info "(viper) Top")

Great, thanks. That is useful to know.

"(viper) Top" still seems like a pretty weird syntax. Just out of
curiosity, is there some explanation? I see that the shell version is
'info filename nodename'. And according to wikipedia info was written
for GNU/linux. So it's a post-linux emacs design? Wouldn't

(info filename &optional nodename)

have been more natural?

Dan

> 

-- 
http://www.stats.ox.ac.uk/~davison

Re: info reference syntax

[Xah Lee]

On Jan 9, 1:12 pm, Dan Davison <davi...@stats.ox.ac.uk> wrote:
> On Fri, Jan 09, 2009 at 08:27:40PM +0100, Lennart Borgman wrote:
> > On Fri, Jan 9, 2009 at 8:22 PM, Dan Davison <davi...@stats.ox.ac.uk> wrote:
> > > What does this syntax mean?
>
> > > ,----
> > > | See Info node `(viper)Top'.
> > > `----
>
> > > Is there some way of using it to immediately access the info node
> > > referred to?
>
> > M-: (info "(viper) Top")
>
> Great, thanks. That is useful to know.
>
> "(viper) Top" still seems like a pretty weird syntax. Just out of
> curiosity, is there some explanation? I see that the shell version is
> 'info filename nodename'. And according to wikipedia info was written
> for GNU/linux. So it's a post-linux emacs design? Wouldn't
>
> (info filename &optional nodename)
>
> have been more natural?

it'd be much better if emacs adopted html as its standard doc format.

It would than just be:

http://gnu.org/doc/emacs/viper/top.html

in this format, every programer understand what it is.  In “(info
"(viper)Top")” or “(viper)Top”, maybe 0.001% of programers knew what
it is.
If we count among emacs users who used emacs for no more than 2 years,
the percentage is perhaps 10%.

Personally, i use emacs daily, staying in emacs most of the time when
using computer, since 1998, and have been using text terminal based
emacs exclusively from 1998 to 2005. I didn't know what is “(info
"...")” until 2005 or so thru chatting in freenode's emacs irc.

Adopting html as standard doc format is easy to do, in fact mostly
just a political gesture. Texinfo can already convert to html, and
most if not all GNU's doc are already presented in html format on
GNU's site.

with adoption of html, people will naturally citing doc by url instead
of “info xyz”. This will help understanding and consequently spread
emacs. For example, if in a discussion in some programing forum,
someone might mention “look (info xyz) in emacs”. Vast majority of
readers wouldn't understand what that is will simply ignore it. But if
html doc is official, then the citing would be “http://gnu.org/doc/
xyz.html”, and those who saw this are very likely to click it.

this wouldn't effect emacs much since emacs can and should still use
info doc in emacs as a integrated system. But down the road, say in 5
years, emacs will need to deprecate texinfo eventually. The HTML/XHTML/
CSS/JavaScript world is literally with few million more users and
developers. Their tools, technical power, extensibility, adoption...
in every area, are few order of magnitude better than textinfo. In
fact, i wouldn't be surprised that modern browser such as Firefox
actually load html doc faster than a comparative info file.

By adopting html now, it can pave the way for emacs transition to
using html/xhtml as integrated doc component. For example, currently
there's w3m for reading html. However, it's some 5 times slower than
Firefox, and some 5 times slower than info reading texinfo. However,
this can be improved. One could have html/xml parser buildin elisp as
c code (or borrowing the rendering engine from firefox), so that
reading html docs in emacs is acceptably fast as current reading in
info.

the integrated nature of info in emacs is really joy to use,
especially programing in elisp. You can lookup any function or keyword
in the lang so easily. However, if the lang is not elisp but perl,
python, php, etc, then it's not so easy because you often have to
download and install a info version of their doc (if it exist at all),
and depending whether the guy who implemented your lang's mode took
the fancy to implement info doc lookup features. (10 years ago, some
mode would still support info doc. Today, as far as i know, nobody
bothered with info version of docs.)

When emacs accepted more html docs, it would mean the integrated doc
feature automatically apply to all langs, such as java, perl, python,
ruby, php, javascript... since their official doc are all html.

  Xah
∑ http://xahlee.org/

☄

Re: info reference syntax

[Eli Zaretskii]

> From: Xah Lee <xahlee@gmail.com>
> Date: Mon, 12 Jan 2009 05:56:51 -0800 (PST)
> 
> it'd be much better if emacs adopted html as its standard doc format.

Unless someone sets out to rewrite all the gazillion Emacs features in
info.el and info-look.el to work with HTML, this ain't gonna happen,
because those features are too useful to give up.

> this wouldn't effect emacs much since emacs can and should still use
> info doc in emacs as a integrated system. But down the road, say in 5
> years, emacs will need to deprecate texinfo eventually. The HTML/XHTML/
> CSS/JavaScript world is literally with few million more users and
> developers.

If you'd talk about XML or DocBook, I could perhaps believed you.  But
the formats you mention cannot replace Texinfo because they are not
powerful enough to support features Texinfo has today, such as
indexing, and don't have a macro system to express useful constructs
such as @defun.  Without these, it's a PITA to write any serious
software documentation.

We _could_ use HTML as an _output_ format (as opposed to source),
which is what I was talking above (makeinfo supports HTML output for a
very long time now).  But to replace the source language with
something else, that something else needs to be at least as powerful
and convenient as Texinfo, and it needs tools to generated both
printed and on-line docs from the same source.

> In fact, i wouldn't be surprised that modern browser such as Firefox
> actually load html doc faster than a comparative info file.

Surprise me! give some measurements for a change.

> Today, as far as i know, nobody bothered with info version of docs.

"Nobody" is, of course, slightly exaggerated, as every GNU package has
Info docs, which in practice means every important piece of software
on a GNU/Linux machine is documented in Info.

Re: info reference syntax

[B. T. Raven]

Dan Davison wrote:
> On Fri, Jan 09, 2009 at 08:27:40PM +0100, Lennart Borgman wrote:
>> On Fri, Jan 9, 2009 at 8:22 PM, Dan Davison <davison@stats.ox.ac.uk> wrote:
>>> What does this syntax mean?
>>>
>>> ,----
>>> | See Info node `(viper)Top'.
>>> `----
>>>
>>> Is there some way of using it to immediately access the info node
>>> referred to?
>> M-: (info "(viper) Top")
> 
> Great, thanks. That is useful to know.
> 
> "(viper) Top" still seems like a pretty weird syntax. Just out of
> curiosity, is there some explanation? I see that the shell version is
> 'info filename nodename'. And according to wikipedia info was written
> for GNU/linux. So it's a post-linux emacs design? Wouldn't
> 
> (info filename &optional nodename)
> 
> have been more natural?
> 
> Dan


This is essentially what it is. Try C-h f info and you read:

"
info is an interactive compiled Lisp function in `info.el'.
It is bound to C-h i, <f1> i, <help> i.
(info &optional FILE-OR-NODE BUFFER)

Enter Info, the documentation browser.
Optional argument FILE-OR-NODE specifies the file to examine;
the default is the top-level directory of Info.
Called from a program, FILE-OR-NODE may specify an Info node of the form
`(FILENAME)NODENAME'.
Optional argument BUFFER specifies the Info buffer name;
the default buffer name is *info*.  If BUFFER exists,
just switch to BUFFER.  Otherwise, create a new buffer
with the top-level Info directory.
"

Re: info reference syntax

[B. T. Raven]

Dan Davison wrote:
> What does this syntax mean? 
> 
> ,----
> | See Info node `(viper)Top'.
> `----
> 
> Is there some way of using it to immediately access the info node
> referred to? Where is it documented?
> 
> Thanks!
> 
> Dan
> 

This seems to be programese for the more natural sequence of keystrokes:

C-h i m viper

This will put you in an info mode buffer with File: viper Node: Top