If you really want a $const (not "use constant"), then I'd go with a tie: 
  sub CONST::TIESCALAR { bless \(my $v = pop), shift }
  sub CONST::FETCH { ${(shift)} }

  tie $x, CONST => 4;

  print "$x\n";
  $x = 7; # run-time error

[download]
--Dave

In reply to Re: How to create a "CONSTANT" by dpuu
in thread How to create a "CONSTANT" by freddo411

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