Did you check CPAN for a module? If there isn't one, you could write one yourself to use the tie mechanism to subvert changing the value of the scalar. perldoc perltie

Here's a quick implementation (untested):

#!/usr/bin/perl

package ConstScalar;

sub TIESCALAR {
   my $class = shift; my $val = shift;
   return bless \$val, $class
}

sub STORE { }
sub FETCH { my $self = shift; return $$self; }

package main;

my $pi;
tie $pi, 'ConstScalar', 3.14159265358979323846;
print "$pi\n";
$pi = 5;                # no effect
print "$pi\n";

[download]

duff

In reply to Re: There is a way to LOCK a SCALAR? by duff
in thread There is a way to LOCK a SCALAR? by gmpassos

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