Hello monks!
I have a question:
Say you have the strings:
$a="ABCDABCDXBCDABCXABCDXXCDABXD";
$b="ABCDABCDABCDABCDABCDABCDABCDABCDABCDABCD";

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If in $a there were no X's, then with a pattern match you would say that $b includes $a. I need to write a pattern match to "ignore" other characters in $a if they are X, but DO NOT erase them. What I mean is that, in the position of X in $a, you could have A, B, C or D, does not matter. I tried the following but did not work:
$a="ABCDABCDXBCDABCXABCDXXCDABXD";
$b="ABCDABCDABCDABCDABCDABCDABCDABCDABCDABCD";

@split_initial=split(//, $a);
for ($i=0; $i<=$#split_initial; $i++)
{
    if($split_initial[$i] ne 'A' && $split_initial[$i] ne 'B' && $spli
+t_initial[$i] ne 'C' && $split_initial[$i] ne 'D')
    {
        $split_initial[$i]="*";
    }
    $seq_final=join('', @split_initial);
}

if ($b=~/$seq_final/) {print "OK\n";}

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I somehow try to insert artificially, the wildcharacter * in $a, so as to "ignore" what's in position of X (because it can be anything between A,B,C or D -it doesn't matter which one) when it searches $b for the presence of $a..
How can I write this pattern match correctly?

In reply to pattern matching with substring containing special character by Anonymous Monk

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