From: Eric Hodel <drbrain@...7.net>
Date: 2007-11-02T12:55:26+09:00
Subject: Re: Import gem to Ruby 1.9

On Oct 24, 2007, at 18:37 , NAKAMURA, Hiroshi wrote:
> Tanaka Akira wrote:
>>> 1. does not have uncertain behavior.  No require 'doc/index'  
>>> problem I wrote at [ruby-core:12792].
>>
>> I agree that mine is not accurate as yours or RubyGems itself.
>>
>> In contrast, the disadvantage of yours are memory consumption and  
>> maintenance.
>
> Don't list 'maintenance' here.  When it's good enough, RubyGems team
> will do it as I wrote in [ruby-core:12810].
>
>> The accuracy and memory consumption is trade off.  For accuracy,  
>> all gemspecs must be loaded and analyzed.  But it consumes memory:  
>> analyzer code and loaded gemspecs.
>>
>> Since RubyGems itself does accurate analysis, its loader can be  
>> conservative.  I think memory consumption justify the  
>> conservativeness.
>
> We've written our thought on this trade off many times each other,
> without concrete grounds.  I still don't have any number to show so I
> don't repeat writing my thought on this again. :-)  No other comments
> from ruby-core.  The decision is up to core team now.
>
> One additional thought for akr's LoadError fallback.
>
> Issue #1 is for solving the problem how we map feature -> path to be
> added to $LOAD_PATH.  Java uses MANIFEST in jar.  RubyGems uses  
> gemspec
> in spec dir.  akr's LoadError fallback uses file system wild globbing.
>  Default Ruby require uses file system accurately.
>
> Can gem command of RubyGems can create a MANIFEST in gemspec dir?   
> Then
> akr's LoadError fallback can grep it for finding rubygems to be loaded
> or not.  It won't be needed as a part of RubyGems though.

It could.  I have considered speeding up RubyGems' require, since it  
scans so many paths looking for files.  I never found it worthwhile  
to implement, since files only get required around startup time.

>>> Your proposal of prelude.rb enables RubyGems.  As I wrote,  
>>> RubyGems uses their 'version selection scheme' independent from  
>>> whether gem method exists or not.  So you cannot use any other  
>>> scheme.  RUBYOPT solution allow you to do the above.
>>
>> I can install any library under site_ruby.  Does RubyGems prohibit  
>> it?
>
> I mean that you can use site_ruby but cannot use others.

If you install a library under site_ruby, a duplicate installation  
with RubyGems will not be loaded without Kernel.gem.

--
Poor workers blame their tools. Good workers build better tools. The
best workers get their tools to do the work for them. -- Syndicate Wars