From: "Ara.T.Howard" <ahoward@...>
Date: 2003-12-03T04:47:08+09:00
Subject: Re: require bug?? (1.8.0)

On Wed, 3 Dec 2003, Andrew Walrond wrote:

> Date: Wed, 3 Dec 2003 00:47:43 +0900
> From: Andrew Walrond <andrew@walrond.org>
> Newsgroups: comp.lang.ruby
> Subject: require bug?? (1.8.0)
> 
> Require is supposed to include each file only once, but if the same physical 
> file is accessed from different paths, it can get included multiple times. Is 
> this the correct behaviour?


yes - see other posts.  i've used something like this as a workaround before

  a.rb
    $lib_a = true
    ...

  b.rb
    $lib_b = true
    ...

  c.rb
    $lib_c = true
    require 'a' unless defined? $lib_a
    require 'b' unless defined? $lib_b
    ...

-a


> 
> Example 1
> 
> File a.rb
> 	puts "a includes b"
> 	require "b.rb"
> 	puts "a includes c"
> 	require "c.rb"
> 
> File b.rb
> 	puts "b includes c"
> 	require "c.rb"
> 
> File c.rb
> 	puts "C INCLUDED"
> 
> $ ruby a.rb
> 	a includes b
> 	b includes c
> 	C INCLUDED
> 	a includes c
> 
> C included once.
> 
> Example 2:
> 
> Change file b.rb
> 	puts "b includes c"
> 	require "./c.rb"
> 
> $ ruby a.rb
> 	a includes b
> 	b includes c
> 	C INCLUDED
> 	a includes c
> 	C INCLUDED
> 
> File c.rb is included twice.
> 
> 
> 

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