What is the right way to initialize a constant in Ruby?

Posted by zbrimhall on Stack Overflow See other posts from Stack Overflow or by zbrimhall
Published on 2010-12-26T01:26:03Z Indexed on 2010/12/26 1:54 UTC
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ruby

|

class-design

I have a simple class that defines some constants, e.g.:

module Foo
  class Bar
    BAZ = "bof"
    ...

Everything is puppies and rainbows until I tell Rake to run all my Test::Unit tests. When it does, I get warnings:

bar.rb:3: warning: already initialized constant BAZ

My habit has been to avoid these warnings by making the constant initialization conditional, e.g.:

...
BAZ = "bof" unless const_defined? :BAZ
...

This seems to solve the problem, but it is a little tedious, and I don't ever see anyone else initializing constants this way. This makes me think I might be Doing It Wrong. Is there a better way to initialize constants that won't generate warnings?

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