From: "\"dooby\" <dooby@...10.karoo." </SPAM@...>, co.uk@...
Date: 2003-01-16T11:20:47+09:00
Subject: Re: trouble understanding const_set()


"Chris Pine" <nemo@hellotree.com> wrote in message
news:132b01c2bb42$737ea330$6401a8c0@MELONBALLER...
> Hello,
>
> I'm trying to understand why the following code is giving me an error.
It
> seems like it isn't finding Foo::Constant (which doesn't exist), but
why
> isn't it looking for Bar::Constant, instead?
>
> As you can see, `self' is Bar, not Foo:
>
>
>  irb(main):001:0> class Foo
>  irb(main):002:1>   def Foo.foo
>  irb(main):003:2>     const_set 'Constant', 'just a string'
>  irb(main):004:2>     puts self.inspect
># irb(main):005:2>     puts Constant

   irb(main):005:2>     puts const_get('Constant')

>  irb(main):006:2>   end
>  irb(main):007:1> end
>  nil
>  irb(main):008:0> class Bar < Foo
>  irb(main):009:1> end
>  nil
>  irb(main):010:0> Bar.foo
   Bar
   just a string
   nil

The change to line 5 averts the [uninitialized constant] error.

Your example shows the answer to a possible supplementary question:
   "Must Bar.const_get('Constant') be used thereafter ?"

>  irb(main):011:0> Bar::Constant
>  "just a string"
>

.... happily, no.


daz