Is that a trick question? By using a look up table aka hash... 

my %map = ( "\t" => '\t' );
my $y = "\t";
print $map{ $y };

[download]

See also Re^3: Generating characters (0 to 255).

After skimming referenced post ... Removed unnecessary chr ord functions.

In reply to Re: reverse interpolation by parv
in thread reverse interpolation by gleeco

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