The length-based approaches are probably a bit faster, but this also seems to work: 

>perl -wMstrict -le
"my $s = qq{\t\t\tX\t\t};
 my $n =()= $s =~ m{ \G \t }xmsg;
 print $n;
"
3

[download]

Update: Removed pointless capture group from regex.

In reply to Re: Simple regex related problem by AnomalousMonk
in thread Simple regex related problem by rachitmohta11

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