This should be a simple problem, but it's stumped me.

I thought Parse::RecDescent would be an easy way to deal with these records, and it's worked fine as long as our customers used the format with a '~' as end-of-record marker, but with just bare newlines it fails miserably.

Can anybody tell me what I'm doing wrong here (in this highly simplified version)? I'm ready to do s/$/~/g, but that's so cheesy :-( 

use Parse::RecDescent;
use strict;

my $text_to_parse_with_tildes = <<EOL;
IEA*1*000002669~
IEA*2*000003333~
EOL

my $text_to_parse_plain = <<EOL;
IEA*1*000002669
IEA*2*000003333
EOL

my $grammar = q{

doc: segment(s)
    { $return =1; }

segment: segmentid "*" element(s /[*]/) segment_end
    {  print STDERR "got a $item{segmentid} ($main::segment_end)\n";
       $return =1;  }

segmentid: /[a-zA-Z0-9]+/
    { $return = $item[1]; }
 
element: /[^*~\n]*/
    { $return = $item[1];} 

segment_end: /$main::segment_end/
    { $return = 1;}
    
};


my $parser = new Parse::RecDescent ($grammar) or die "Bad grammar!\n";

#tildes as record-ends, works fine
$main::segment_end  = '~\n';
defined $parser->doc($text_to_parse_with_tildes)  #works fine
   or print "parse failure! bad text!\n";

#plain record-ends, fails miserably
$main::segment_end = '\n';
defined $parser->doc($text_to_parse_plain)  #fails
   or print "parse failure! bad text!\n";

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In reply to newlines in Parse::RecDescent by kgoess

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