if($ip_no =~ /\D/ || $ip_no=~ //)

[download]

That is the same as saying: 

 if($ip_no =~ /\D/ || $ip_no=~ /\D/)

[download]

Because an empty match operator uses the last successfully matched regular expression.

In reply to Re^3: reprompt user input, until validation pass by jwkrahn
in thread reprompt user input, until validation pass by ganeshfriends

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