in reply to Re: multiline regex: heredoc vs. reading file
in thread multiline regex: heredoc vs. reading file

One line? From page 147 of 'Programming Perl' -

/m Let ^ and $ match next to embedded \n.
/s Let . match newline and ignore deprecated $* variable.

Wouldn't that mean it would look for multiple lines?

  • Comment on Re^2: multiline regex: heredoc vs. reading file

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Re^3: multiline regex: heredoc vs. reading file
by ysth (Canon) on Jan 25, 2006 at 18:06 UTC
    /m changes where ^ and $ can match; /s changes what . can match. Since you don't have any of ^, $, or . in your regex, the flags do nothing.

    The problem is that you have a regex that only matches multiple lines, but you are trying to match each line of the file against it individually, and of course none of them do match.

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Re^3: multiline regex: heredoc vs. reading file
by ikegami (Patriarch) on Jan 25, 2006 at 18:02 UTC
    The problem is not with the regexp. The problem is that $_ only contains one line. See my earlier post in this discussion for more details.
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[d/l]
      OK, so I changed the while loop to contain the following, and still get the same thing - 
        $_ .= <TEST>;
    if (m{
          \w+\n
          .+
          \w+
         }msx) {
        print "reading file test: The line \n$_\nmatches.\n";
    }

      [download]
      I would think that
      a) $_ .= <TEST>; would be equivalent to your $text = <$test_fh>; line, and
      b) replacing \n with .+ utilizes the /s,

      correct?

[reply]
[d/l]
        Now, $_ contains two lines, but you need three with the data you showed. Also, $_ .= <TEST> could attempt to read past the end of the file, but you don't check for that.
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