This is a bit of an odd request, but does anyone know how i would find
what file Ruby is using to define an object in? For instance if i had
a few libraries in my include path and they defined the (ever useful)
classes Foo, Bar, and Baz is there anyway to find out from within ruby
that Foo is defined in the file /usr/local/lib/ruby/gems/1.8/gems/
foo-1.0.0/lib/foo.rb or wherever?
The best i could come up with would be a rather brute force approach
to searching through the files found in $: and this just seems
horribly slow and prone to explosions. Just wondering if someone out
there who has a better understanding of Ruby’s underbelly might have a
better idea.
/Geoff
There is a Kernel method called “caller” that can help you here. It
returns
the current execution stack in the “file:line” format, so if you need to
know what file a method is define in, you can use the “caller” method to
show you.
Mark
gparsons wrote:
This is a bit of an odd request, but does anyone know how i would find
what file Ruby is using to define an object in? For instance if i had
a few libraries in my include path and they defined the (ever useful)
classes Foo, Bar, and Baz is there anyway to find out from within ruby
that Foo is defined in the file /usr/local/lib/ruby/gems/1.8/gems/
foo-1.0.0/lib/foo.rb or wherever?
The best i could come up with would be a rather brute force approach
to searching through the files found in $: and this just seems
horribly slow and prone to explosions. Just wondering if someone out
there who has a better understanding of Ruby’s underbelly might have a
better idea.
/Geoff
This might not be fully general, but works in the basic case. If
SCRIPT_LINES__ is defined as a hash when a file is loaded, the lines of
the file are stored as an array under the key of the filename.
SCRIPT_LINES__ = {}
require ‘foo’
def defining_files(klass)
files = []
SCRIPT_LINES__.each do |filename, lines|
if not lines.grep(/class\s+(\S+::)*#{klass.to_s}/).empty?
files << File.expand_path(filename)
end
end
files
end
defining_files(Foo)
best,
Dan
On 29.05.2007 22:22, gparsons wrote:
there who has a better understanding of Ruby’s underbelly might have a
better idea.
Note that the caller approach either requires to manipulate the class
that you are looking for or you need to know that it has a method that
will accept a block which you can use to inject your “locating code”.
Given the frequency (or rather /in/frequency) with which this comes up
here it seems that most people are OK with the brute force approach. 
Kind regards
robert
Daniel L. wrote:
This might not be fully general, but works in the basic case. If
SCRIPT_LINES__ is defined as a hash when a file is loaded, the lines of
the file are stored as an array under the key of the filename.
SCRIPT_LINES__ = {}
This is the most obscure and arcane bit of ruby knowledge I have learned
in a loooong time. Bravo
Daniel
Daniel DeLorme wrote:
This is the most obscure and arcane bit of ruby knowledge I have learned
in a loooong time. Bravo
Thank Dave T… I just decided to read Programming Ruby Part Three
from cover to cover yesterday.
Dan