If your one long string is coming from a file, you don't have to use a new line to divide it up into sentences. You can set $/ to any string, including a period - see perlvar for details. This has the additional advantage of not consuming large amounts of memory by trying to slurp in a long chunk of text without any new lines all at once.

If the one long string is coming from elsewhere, you can still make use of $/ by opening an input stream on a string. Here's an example of a solution that lets you freely choose the starting words, ending words, and end of sentence marker. It uses both $/ and a string turned into an input stream.

use strict;
use warnings;

sub findWords {
  my ($sText, $sEndSentence, $reStart, $reEnd)=@_;

  local $/=$sEndSentence;
  open(LONG_STRING, "<", \$sText) || die "Can't open string";
  while (my $line = <LONG_STRING>) {
    chomp $line;
    if (($line =~ $reStart) && ($line =~ $reEnd)) {
      print "match: $line\n";
    } else {
      print "no match: $line\n";
    }
  }
}

findWords("a b c.  Nullam est libero.Nullam est augue", '.'
          , qr(^\s*Nullam)
          , qr((?:libero|augue)\s*$));

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Best, beth

In reply to Re: Parse a large string by ELISHEVA
in thread Parse a large string by 1001jrlight

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