• Login
Community
  • Login

Please remove PCRE-compatible from features

Scheduled Pinned Locked Moved General Discussion
5 Posts 4 Posters 3.4k Views
Loading More Posts
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • S
    Shean Gibber
    last edited by Sep 24, 2017, 11:14 PM

    Hello there, don’t know where the development issues are hosted, but please pass this along to them:

    • Please remove PCRE compatible tag from features, that’s not true, it does not handle lookbehinds. Either remove the tag, or specify that it does not handle lookbehinds, specifically. That’s misleading.

    Thanks!

    C 1 Reply Last reply Sep 25, 2017, 10:10 AM Reply Quote 0
    • C
      Claudia Frank @Shean Gibber
      last edited by Sep 25, 2017, 10:10 AM

      @Shean-Gibber

      I don’t really understand what you mean but I assume it should be reported here anyway.

      Cheers
      Claudia

      1 Reply Last reply Reply Quote 0
      • S
        Scott Sumner
        last edited by Sep 25, 2017, 11:56 AM

        http://docs.notepad-plus-plus.org/index.php/Regular_Expressions mentions “PCRE” (Perl Compatible Regular Expressions) six times, the first of which is: “Notepad++ regular expressions use the standard PCRE (Perl) syntax…”

        This may originate from the release notes of version 6 of Notepad++ (https://notepad-plus-plus.org/download/v6.0.html ) which state: “PCRE (Perl Compatible Regular Expressions) is supported.”

        Recent Notepad++ versions support Boost-compatible regular expressions, not PCRE. I don’t know the complete history–maybe in the beginning (6.0) the PCRE flavor of regex was supported? Or maybe it was always Boost’s engine and it was just referred to incorrectly in the beginning, and that has been allowed to persist?

        Regardless, the OP is correct – “PCRE” has no business being in the documentation.

        That being said, I’m not sure what the OP @Shean-Gibber is meaning with “does not handle lookbehinds”. Notepad++'s Boost regex engine DOES handle lookbehinds; both positive lookbehinds and negative lookbehinds. Examples:

        • Positive lookbehind: (?<=a)b matches a “b” only when preceded by an “a”
        • Negative lookbehind: (?<!a)b matches a “b” that is NOT preceded by an “a”

        Lookbehinds must be of fixed length; it is hard for a regex engine to go backwards in a variable-length way.

        1 Reply Last reply Reply Quote 0
        • M
          MAPJe71
          last edited by Sep 25, 2017, 3:33 PM

          Notepad++ uses the Boost Regex library which is a PCRE (Perl Compatible Regular Expression) library. The confusion is the result of a different regular expression library named “PCRE”.

          S 1 Reply Last reply Sep 25, 2017, 3:46 PM Reply Quote 0
          • S
            Scott Sumner @MAPJe71
            last edited by Sep 25, 2017, 3:46 PM

            And we propagate the confusion… :-D

            1 Reply Last reply Reply Quote 1
            5 out of 5
            • First post
              5/5
              Last post
            The Community of users of the Notepad++ text editor.
            Powered by NodeBB | Contributors