Two problems with the substitution you tried: 

$temp = s|_|.|;

[download]

First, you need a tilde: $temp =~ s///

Second, you need the /g operator so that more than just the first "_" is replaced.

 $temp =~ s|_|.|g; 
sub sk{ return unless $in = shift;
        $in =~ s!(.)$!!; print $1; sk($in)}
sk("gro.alubaf@yehaf");

[download]

In reply to Re: substitution in a string by skillet-thief
in thread substitution in a string by s_gaurav1091

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