bug#880: 23.0.60; c-mode indentation and php

[Alan Mackenzie]

Hi, Lennart,

On Wed, Sep 03, 2008 at 11:34:04PM +0200, Lennart Borgman (gmail) wrote:
> In php-mode.el (not yet a part of Emacs, but has been discussed for
> inclusion) c-indent-line is used for indentation.

UUURRRKKK!!!

> That works nicely for the php code part of a php template page, but
> there is a disturbing glitch that probably can be fixed.

> Constructs like the one below are rather common.

>    if (1) {
>  ?>
>   ...
>  <?php
>      }

> If you try to indent the line with the single "}" in c-mode it does not
> get aligned with "if (1) {". I have narrowed this down to

>    if (1) {
>  ?php
>      }

> Adding a semicolon after "?php" makes everything work.

Without the semicolon, the close brace is on a "statement continued"
(statement-cont) line.

> Is the current indentation behaviour in this case useful in some way?

Yes.  I'm characterising your "in this case" as "after a line lacking ;
or }".  It's essential to normal C indentation.  E.g.:

    a = b + c // no semicolon
        + d ; // statement-cont (use C-s C-c) gets more indentation. 
        
> Is there some option to change it?

Yes.  Write a PHP-specific function to determine whether a line ends with
a "virtual semicolon", and set `c-at-vsemi-p-fn' to this function.  This
mechanism is used for AWK Mode, and is described in detail in cc-defs.el
(search for "virtual").

> The example came from a bug report/question for nXhtml:

>   https://answers.launchpad.net/nxhtml/+question/43320


> In GNU Emacs 23.0.60.1 (i386-mingw-nt5.1.2600)
>  of 2008-09-03
> Windowing system distributor `Microsoft Corp.', version 5.1.2600
> configured using `configure --with-gcc (3.4) --no-opt --cflags
> -Ic:/g/include -fno-crossjumping'

-- 
Alan Mackenzie (Nuremberg, Germany).