From: matz@... (Yukihiro Matsumoto)
Date: 2001-09-19T01:21:51+09:00
Subject: [ruby-talk:21340] Re: nested require files need path internally

Hi,

In message "[ruby-talk:21331] Re: nested require files need path internally"
    on 01/09/19, Paul Brannan <pbrannan@atdesk.com> writes:

|The problem with doing this is that if I have a directory structure like
|this:
|
|   |
|   +- foo
|   |  +- foo.rb
|   |  +- bar.rb
|   |
|   +- mystuff.rb
|
|And in mystuff.rb I have:
|
|  require './foo/foo.rb'
|
|And in foo.rb I have:
|
|  require './bar.rb'
|
|Then the require will fail, because bar.rb is not in the current
|directory.

I'm not sure what is your point.  If you really want to read from the
current directory hierarchy (which is pretty unreliable), you can
prepend "." to $LOAD_PATH variable.

|Additionally, part of the problem that was brought up was that if I do:
|
|  require 'foo.rb'
|  require 'foo'
|
|both of these will cause the same file to be required; the file will, in
|fact, be loaded twice.  This is evident by the following simple program:
|
|  if not defined?(x) then x = '' end
|  x << './'
|  require "#{x}#{__FILE__}"
|
|This will load the SAME FILE over 100 times.

Wait a second.  

|  require 'foo.rb'
|  require 'foo'

does not load twice.  In your example, you loaded a file using
different path.  Normalizing loaded path is a good thing to see, but I
don't think it's mandatory.

|Ideally, require would do the following:
|
|  1) Check for the ./ prefix; if it is there, look in the same directory
|     as __FILE__.

I don't agree with this.  This changes "." semantics.

|  2) Check to see if the file is a symlink; if it is, get the name of the
|     real file being required.  Repeat as necessary.
|  3) Find the full pathname of the file being required before marking the
|     file as already having been required.

I'm not sure above 2) and 3) are worthy enough, considering loading
from current working direcotry is not recommended.

							matz.