#!/usr/bin/perl use strict; use warnings; package protected; # constant data that doesn't complain, just doesn't change. # We could have a flag to allow a protected to store a value once; # We could have a "new" subroutine to hide the tied'ness. # Then usage would look like: # use protected; # my $ONE = protected->new; # $ONE = 'one'; sub TIESCALAR { my $class = shift; my $data = shift; return bless { data => $data }, $class; } sub FETCH { return $_[0]->{data} } sub STORE { return $_[0]->{data} } package main; my $THREE; tie $THREE, 'protected', "three "; $THREE = "four"; chomp $THREE; print "\$THREE >$THREE<", $/;