$num='36737';
$idx=0;
while($num=~m/[0-9]{$idx}/)
{
       $idx++;
}
$idx--; # adjusment to get correct answer
print "\n$num has $idx digits ";

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Is this what you wanted?

In reply to Re: Calculating variable {n} in regex match by cheekuperl
in thread Calculating variable {n} in regex match by atreyu

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