[Nano-devel] disable a time-consuming multiline regex?

[Benno Schulenberg]

Hi all,

The following regex in c.nanorc is very time-hungry:

  # Multiline strings.  This regex is VERY resource intensive!
  color brightyellow start=""(\\.|[^"])*\\[[:space:]]*$" end="^(\\.|[^"])*""

For example, run 'src/nano --cons +4444 src/winio.c',
then press and hold ^Y.  See how the flying by of the
pages is fairly smooth.

Then exit nano and run the same command again, and
type ^Y ^K.  Then press and hold ^Y.  See how after
a few seconds the scrolling begins to stutter and
pause (at least here it does, on a 1.6 GHz Atom).

Maybe that string should be commented out by default?
(When I do so, scrolling becomes fluid.)

Also, the regex doesn't work fully correctly.
For example, run 'src/nano imperfect.c' and type:

"one
two
three"

The string isn't coloured, which is correct, because backslashes
are missing.  Now type a backslah after "one" -- all three words
are coloured.  But that should happen only when there is also a
backslash after "two".  Nano's regexes are not capable of expressing
this, so maybe also therefore such an imperfect matcher should be
disabled?

Benno

-- 
http://www.fastmail.com - The way an email service should be