Re: Require Namepaces and RubyGems' effect on LoadPath problem

Sorry for the delay. I was working hard on an improved implementation.

On 9/26/05, mathew <[e-mail]> wrote:

> XML has namespaces so that there can be multiple elements with the same
> base name. Ruby 'require' already supports that--you can have require
> 'foo/set.rb' and require 'bar/set.rb', the same way you can have
> <foo:set> and <bar:set>.

Sort of. XML namespaces are references. So foo: and bar: could
actually be referencing the same space, in which case they'd be the
same 'set'. That's kind of what Require Namespaces does: It allows you
to require a 'name' that will be searched for in alternate/multiple
directories.

> I still don't understand how this namespace proposal improves things,
> other than to reduce typing. Can you give an example?

I use it to organize a very large library. I've organized the lib
according to principles that make sense for development --in this case
it's a collection of general purpose libs so I've put classes in one
directory, modules in another, etc. But I don't want the end user to
have to "path down" so far, so the namespace allow all the folders to
be grouped together. So intead of:

  mylib/classes/foo.rb
  mylib/module/bar.rb

the user can just do:

  mylib/foo.rb
  mylib/bar.rb

Morover, it makes it easy to add aliases. For instance this could work too:

  mylibs/foo.rb
  mylibs/bar.rb

As things stand there is no way to do this. One could use symlinks but
you'd have to maintain them and they are not cross-platform.

> >But that's the point. I'd rather not maintain a single directory with
> >100+ files? No, I'd rather break them up into some reasonable
> >categories, even though I want the end user to be able access them
> >through one interface.
> >
>
> What's wrong with having a file  mylib/integer.rb  which simply consists of
>
> require 'mylib/system/byte.rb'
> require 'mylib/system/word.rb'
> require 'mylib/special/prime.rb'
> require 'mylib/positive.rb'
> require 'mylib/negative.rb'

On this side of things the problem is the attachment of an absolute
name, 'mylib'. Using namrspaces one can use relative naming. So for
example mylib/integer.rb could just be:

  require 'system/byte.rb'
  require 'system/word.rb'
  require 'special/prime.rb'
  require 'positive.rb'
  require 'negative.rb'

Moroever one could actually move the whole lib to yourlib/ and it
would work just as well. No need to adjust every file's require
statements.

T.