Why global regex doesnot work as tested on debug interactive: 
$str='kklmn;
$str=~ s/(?=(kkl))(?(1)\g1|mn)/***/g;
print "$str\n";

***mn

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only first is processed, what is the point of failure here ?
Please help and thanks before

In reply to Doing by global regex does not work as on debug by Anonymous Monk

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