From: Robert Klemme <shortcutter@...>
Date: 2011-03-16T21:33:32+09:00
Subject: Re: Proposal: require to return path to loaded file

On Tue, Mar 15, 2011 at 9:29 PM, Alex Young <alex@blackkettle.org> wrote:
> If you're doing anything at all involved with $LOAD_PATH, it can be a
> right pain trying to track down which file was actually loaded. It would
> *really* help debugging if require returned the full path to the file.
>
> Would this break anything? Alternatively, is there any other way to get
> at this information?

Somewhat similar

$ ruby19 -e 'l=$LOADED_FEATURES.dup;require "CSV";puts($LOADED_FEATURES - l)'
/opt/lib/ruby/1.9.1/forwardable.rb
/opt/lib/ruby/1.9.1/English.rb
/opt/lib/ruby/1.9.1/date/format.rb
/opt/lib/ruby/1.9.1/date.rb
/opt/lib/ruby/1.9.1/i386-cygwin/stringio.so
/opt/lib/ruby/1.9.1/csv.rb
$

> While I admit that I haven't exactly tested it extensively, it's about
> as simple a patch as you can get. In 1.8.7-p302, it's:
>
>
> diff --git a/eval.c b/eval.c
> index 7156c06..ca4d99b 100644
> --- a/eval.c
> +++ b/eval.c
> @@ -7455,7 +7455,7 @@ rb_require_safe(fname, safe)
>                    break;
>                }
>                rb_provide_feature(feature);
> -               result = Qtrue;
> +               result = path;
>            }
>        }
>     }
>
> Running this gives (obviously):
>
> $ ruby -e 'p require "socket"'
> "/home/alex/.rvm/rubies/ruby-1.8.7-p302/lib/ruby/1.8/i686-linux/socket.so"

Looks good to me.  You only must be aware that you see only one file
but not all other files loaded along the way.  But for that you could
use the approach from above.

> From a cursory inspection, it looks like the same idea ought to apply to
> load.c in 1.9.2. Thoughts, anyone? Given that it's this simple and I
> can't be the first person to have thought of it, is there a reason it's
> the way it is?

Why not? +1

Kind regards

robert

-- 
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