Hello Brothers,

I am trying to parse a file using the regex below. In the case of a failed match, what I would like to do is be able to determine how much of the string was matched before the regex engine gave up so that I can give a useful error message. But since 'pos' only gets set when there is a completed match, the code below will not do what I had hope it would. Do I have to break my regex into multiple pieces and use \G or is there a better way?

Thanks,

Jim 


    my $param_rx      = '[^),]+';  
    my $list_start_rx = '\s*\(\s*'; 
    my $list_end_rx   = '\s*\)\s*'; 

    $_ = $stmt;

     /^\s*                             
     (\S+)                             
     \s+                               
      (\S+)                             
     $list_start_rx                    
     ($param_rx(?:\s*,\s*$param_rx)*)? 
     $list_end_rx                      
     =\s*                              
     (?:0x)?\d+               
     \s*;\s*$                          
    /cgxo; 

    if (pos() != length($stmt)) {
      print "\n$stmt\n";
      print ' ' x pos();
      print "^<-- Parse failed here (column " . pos()  . " of " . leng
+th($stmt) . ")\n";

      &error ($ARGV, $line_num, 'Exiting');
    }

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In reply to Parsing with regular expressions by Anonymous Monk

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