From: Joel VanderWerf <vjoel@...>
Date: 2008-05-24T11:29:37+09:00
Subject: Re: Prevent ruby constant variables from changing?

Dave Bass wrote:
> Pe単a, Botp wrote:
>> i too had this problem, and the closest i can get is to wrap the 
>> constants in a module and then freeze the module.
> 
> I was inspired by Perl's use of subroutines as wrappers for constants to 
> come up with the following technique. It doesn't involve modules or 
> freezing:
> 
> irb(main):001:0> def self.Const
> irb(main):002:1>   1
> irb(main):003:1> end
> => nil
> irb(main):004:0> self.Const
> => 1
> irb(main):005:0> self.Const = 2
> NoMethodError: undefined method `Const=' for main:Object
>         from (irb):5
> irb(main):006:0> self.Const
> => 1
> 
> Anyone see problems? It at least avoids accidental modification of a 
> constant, and it's simple.

you have to stick to the self.Const syntax though.

def self.Const; 1; end
Const = 2
p Const

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407