Re: What's your favourite *under_publicized* editing feature of Emacs?

[Stefan Monnier]

>> I set 'grep-mode' on my log file (which follow GNU
>> error coding convention). On 50-100 KiB logs it take
>> 10 sec to highlight matches. On larger files I type
>> C-g to stop matching for highlighting.

You may want to try the Emacs trunk's version of compile.el (I think
it'll work with Emacs-23 as well).  It should help out by being more
lazy (e.g. it'll still takes 10s to parse the file when you jump to the
end of it, but it should open instantaneously because it'll only need to
parse the first page for that).

> And I realize that compilation-mode is dumb as it try
> set on all matched file/line pairs text properties to
> allow move to another file by RET.

compilation-mode indeed does more work than I'd like at the "highlight"
time, and some of that work could indeed be delayed to the moment the
user hits RET on a line.  But my impression is that most of the time is
spent regexp-matching (i.e. looking for matches) anyway, so moving this
work won't make much difference if any.  IOW my impression is that if
your code is faster it's because it uses either more efficient regexps,
or fewer regexps.

>     ("^\\([^:]+\\):\\([[:digit:]]+\\):[^

E.g. this regexp is more efficient than the one used by grep.el, by
disallowing : in file names (resulting in a backtrack-free regexp).


        Stefan