I am having a problem with defining a grammar for Parse::RecDescent - The format which I am parsing is relative simple and consists of a textfile with opening tags defined as <MT\d+> (for example, <MT100> or <MT57>). These tags may be closed by one of two events:

There may or may not be any information between the opening and closing of a tag, but the presence of such tags is still important.

So far I have been able to build the following grammar for Parse::RecDescent:

File:      Tag(s) EOF

Tag:
          | MT Element EOT
                { 
                  print "MT:  ", $item[1], "\n";
                  print "     ", $item[2], "\n";
                }
          | MT Element
                { 
                  print "MT:  ", $item[1], "\n";
                  print "     ", $item[2], "\n";
                }
          | MT EOT
                { 
                  print "MT:  ", $item[1], "\n"; 
                }
          | MT
                { 
                  print "MT:  ", $item[1], "\n"; 
                }
          | <error>

MT:         /<MT\d+>/

Element:    /[^\/\n]+/

EOF:        /^\Z/
EOT:        /\//

[download]

But the problem is that the Element token is too greedy and will eat up until the end of the line, swallowing any other tags. I have also tried to use the ...TOKEN construct within the grammar with no luck. What am I doing wrong?

In reply to Difficulties defining a grammar for Parse::RecDescent by Anonymous Monk

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