in reply to Usage of grep on a file

Probably you want to combine Regexp::Assemble with inplace edit and do something like:

use Regexp::Assemble;
  
my $ra = Regexp::Assemble->new;
$ra->add ($_) for @matchArray;

my $re = $ra->re;

@ARGV = ('filename');
$^I = '.bak';

while (<>) {
  print if m/$re/;
}

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DWIM is Perl's answer to Gödel

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Re^2: Usage of grep on a file
by tsk1979 (Scribe) on Apr 07, 2006 at 07:30 UTC
    Thanks. If I dont want to use that module then do I do this? instead of that I can have 
    $full_string = "";
foreach (@match_array) {
  $full_string = $full_string."|".$_;
}

    [download]
    then do a grep with $fullstring as the match pattern?
[reply]
[d/l]

      If the file is large don't slurp it, use a loop to process a line at a time. You could do it this way:

      #open file
#open outFile

while (<file>) {
  my $line = $_;
  my $match = 0;

  for (@matcharray) {
    ($match = 1), last if $line =~ m/$_/;
  }
  print outFile $line if $match;
}

      [download]
      DWIM is Perl's answer to Gödel
[reply]
[d/l]
      #  ... which is same as ...
$full_string = join '|' , @match_array;

      [download]
[reply]
[d/l]

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