From @moritz

23​:15 <@​moritz_> rakudo​: say 'foto' ~~ /<-[\t]>+/
23​:15 < p6eval> rakudo 3075a5​: OUTPUT«fo␤»
23​:15 * moritz_ bangs head against wall

should match the full string, of course...

From @moritz

The bug seems to be located in nqp-rx file src/Regex/P6Regex/Actions.pm
method cclass_elem​:

  for $<charspec> {
  if $_[1] {
  ...
  }
  else { $str := $str ~ $_[0]; }
  }
  $past := PAST​::Regex.new( $str, :pasttype('enumcharlist'),
:node($/) );

The $_[0] captures the 't' in a regex like <[\t]>, and concatenating it
like this seems oh so wrong, and explains why nqp-rx thinks <[\t]> is
the same as <[t]>.

I'm not sure what the best way of fixing this is; the logic for handling
backslash escapes is already present in method backslash​:sym<t> etc.;
maybe this can be factored out somehow to avoid code duplication.

@moritz - Status changed from 'new' to 'open'

From info@syntax-k.de

Hi!

I'm trying to do this​:

"a\nb" ~~ m/<-[\n\#\ \t]>+/

and it matches the whole string, while

"an\nb" ~~ m/<-[\n\#\ \t]>+/

matches "a" only. The positive cases behave consistently.

The data file I'm parsing can have about anything in a "word" that is not
whitespace, but it does allow #-style comments. The above regex doesn't
work, since \n and \t do not exclude newline/tab but "n" and "t". Isn't
this inconsistent with the "escaped letters are metacharacters" rule?

While searching for information, I found little about if/how this is
supposed to work, neither in S05, the spectests, nor the allmighty
internet. The only hint that someone else thought it should work this way
was the perl5 module Perl6​::Rules, which gives <[\w]-<digit>> as an
example. So this may actually be an oversight in S05, or something totally
obvious which I didn't find.

--
Mit freundlichen Grüßen,

  Jörg Walter

From @jnthn

On Sat Mar 20 15​:17​:42 2010, moritz wrote​:

23​:15 <@​moritz_> rakudo​: say 'foto' ~~ /<-[\t]>+/
23​:15 < p6eval> rakudo 3075a5​: OUTPUT«fo␤»
23​:15 * moritz_ bangs head against wall

should match the full string, of course...

This was fixed a bit ago​:

say 'foto' ~~ /<-[\t]>+/
=> <foto>

Tagging testneeded, though we may already have some.

/jnthn

From @moritz

We have indeed test coverage, so closing ticket.

@moritz - Status changed from 'open' to 'resolved'