From: Joel VanderWerf <vjoel@...>
Date: 2004-12-29T07:04:48+09:00
Subject: Re: Namespaces, inverted

Robert Klemme wrote:
...
> We have Kernel#load [1] with a similar functionality already.  Currently 
> it accepts an additional parameter to enforce wrapping of the file in an 
> anonymous module.  That could be extended to accept a module as well; 
> that then would be the module used.  Then we can do
> 
> load "foo.rb" # not wrapped
> load "foo.rb" # wrapped in an anonymous module
> load "foo.rb", MyExternal # wrapped in MyExternal

Wrapping is a nice idea (see raa:script for one approach), but the 
wrapped lib will break if it depends on modifying classes or modules in 
the global scope or defining global methods (the Complex example in my 
previous email).

There is the idea the OP mentioned of parsing input files and rewriting 
them to be explicit about the scope of definitions, automating the 
kludgy hack I proposed for complex.rb. But that will break if the lib 
uses dynamic code generation.

Maybe library writers should follow a standard of making their code 
explicit about namespaces:

1. If you open and existing class, give an absolute path to it:

   class ::Integer

rather than

   class Integer

2. Global methods defs should be wrapped like this:

   class ::Object
     def global_meth ... end
   end

3. References to constants (not just classes and modules) defined in the 
lib should be relative:

   class Foo
   end

   f = Foo.new

and not absolute:

   f = ::Foo.new

(although I can't imagine that many libs have this problem).

4. Anything else to protect the lib from breakage when wrapping?