in reply to Regex boundary match

Did you try a negative lookahead assertion to exclude the dash ?

update

 DB<21> $test = qq|Some test. This is a test-with a dash. We want to m
+atch test here|

 DB<22> x $test =~ /\b(test)(?!-)\b/g
0  'test'
1  'test'

 DB<23> print pos($test),":$1\n" while $test =~ /\b(test)(?!-)\b/g
9:test
60:test

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Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

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Re^2: Regex boundary match (updated demo code)
by ultranerds (Hermit) on Feb 08, 2020 at 14:08 UTC
    Thanks. I ended up with ([^\-]). Is your version quicker? Or negligible difference? (its going to be run quite a lot of times)
[reply]
[d/l]
      I ended up with ([^\-]). ... difference?

      It depends on exactly what you want.  ([^\-]) requires a character match and consumes a character. As LanX pointed out,  ([^\-]|$) consumes a character if it can. Neither seem to do what you want: 

      c:\@Work\Perl\monks>perl -wMstrict -le
"my $s = 'test atest atested tested test- -test test .test test. test'
+;
 ;;
 $s =~ s/\b(test)([^-])/DONE/g;
 print qq{'$s'};
"
'DONEatest atested DONEd test- -DONEDONE.DONEDONE test'

c:\@Work\Perl\monks>perl -wMstrict -le
"my $s = 'test atest atested tested test- -test test .test test. test'
+;
 ;;
 $s =~ s/\b(test)([^-]|$)/DONE/g;
 print qq{'$s'};
"
'DONEatest atested DONEd test- -DONEDONE.DONEDONE DONE'

      [download]
      Maybe this does: 
      c:\@Work\Perl\monks>perl -wMstrict -le
"my $s = 'test atest atested tested test- -test test .test test. test'
+;
 ;;
 $s =~ s/\b(test)(?!-)\b/DONE/g;
 print qq{'$s'};
"
'DONE atest atested tested test- -DONE DONE .DONE DONE. DONE'

      [download]

      Update: Just noticed from the timestamps that ultranerds already decided to go with LanX's suggestion. :)

      Give a man a fish:  <%-{-{-{-<

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