I need help understanding a warning I got and correct my syntax on the ~~ operator match.

Also, I appreciate any commnents on the code and method(improving, provide possible oversight on code, etc..)

Again, I am learning so much with all of your help and advice

find myself liking Perl...today ;-)

question 1 I don't understand why on INDEX, the warning says $string is undef? and I also had to declare it again as "my" when I did on pragma.

question 2 whys is the '~~" operator method it's not working

use strict;
use warnings;
use diagnostics;


my @char;
my $art;
my $string = 'abcdefghijk'; 
my %match = (bc => "Michelangelo", efg => "Raffaello",de => "Caravaggi
+o",ijk => "Tintoretto",hij=>"Leonardo",);

@char = split //,$string;


#check that the substring is in hash; 
foreach $art (keys %match){
  if ($string=~/$art/){
      print "There's a match in the string to $art =>", $match{$art}++
+,"\n";
      }    
    }

 #now using GREP
 
 foreach $art (keys %match){
     if (my $seen= grep {$string =~ $art}$match{$art}) 
     {
         print "I have seen using GREP $art=>",$match{$art},"\n"; 
     
     }
 }

#using ~~ match operator

foreach $art (keys %match){
print "this is \~~ $art=> ",join('',$match{$art}) if /$string/i ~~$art
+;    
    }

#using INDEX()

foreach $art (keys %match){
    print "this is INDEX $art =>",join('',$match{$art}),"\n", if index
+ my $tring,$art;
    }

[download]

In reply to Re: find a substring of unknow lenght if it is in a hash by perlynewby
in thread find a substring of unknow lenght if it is in a hash by perlynewby

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