Hi,

I am writing a program that extracts information from websites. As the websites all use the same format, I use a loop to extract the information I am interested in. For some documents, I get the error message 

substr outside of string at extract.pl line 187
use of uninitialized value in string eq at extract.pl line 182
use of uninitialized value in concenation (.) at extract.pl line 185
use of uninitialized value in concenation (.) at extract.pl line 185

This message is then repeated endlessly (presumably because of the loop?). What causes the "substr outside of string" warning?

Here is the code the message is referring to, the first line is number 178: 

 if ($content_sub2=~'Rapporteur') { 
     $ch=substr($', $ch_count, 1);
     my $ch_count2=0;
     while ($ch_count2<2) {
      if ($ch eq" ") { 
       $ch_count2++;
      }
      $d_ep_rap=$d_ep_rap.$ch;
      $ch_count++;
      $ch=substr($', $ch_count, 1);
     }
    }

[download]

Thank you

In reply to Substr warning by New Novice

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