Successful matching resets the $1, even if there's nothing to capture. Therefore, $1 is Barney in the pattern, but it's empty in the replacement part, because the pattern ($1) doesn't capture anything.

To make the captured string survive a match, assign it to a normal non-magical variable: 

my $who = $1;
s/$who/\U$who/gi;

[download]
map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to Re: Having issues with substitutions by choroba
in thread Having issues with substitutions by catfish1116

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