Is there an easy way to discover the path to a “require”-ed module (assuming it’s a .rb file)?
Ie, is there some way to find out where the interpreter would find fred.rb if I said
require ‘fred’
TIA
Harry O.
You may want to look at rextra… I found this
def required
result =
$".each do |file|
$:.each do |path|
if File.exists?( path + ‘/’ + file )
result << (path + ‘/’ + file)
next
end
end
end
result
end
irb(main):001:0> require ‘rextra’
…/rextra.rb:126: warning: *' interpreted as argument prefix ../rextra.rb:369: warning: ’ interpreted as argument prefix
(eval):4: warning: *' interpreted as argument prefix (eval):4: warning: ’ interpreted as argument prefix
(eval):4: warning: *' interpreted as argument prefix (eval):4: warning: ’ interpreted as argument prefix
(eval):4: warning: *' interpreted as argument prefix (eval):4: warning: ’ interpreted as argument prefix
=> true
irb(main):002:0> required
=> [“/home/neoneye/stow/ruby/lib/ruby/1.8/irb.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/e2mmap.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/init.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/context.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/workspace.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/extend-command.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/ruby-lex.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/slex.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/ruby-token.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/input-method.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/i386-freebsd5.1/readline.so”, “/home/neoneye/stow/ruby/lib/ruby/1.8/irb/locale.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/tempfile.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/delegate.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/tmpdir.rb”, “./rextra.rb”, “/home/neoneye/stow/ruby/lib/ruby/1.8/i386-freebsd5.1/st
ringio.so”]
irb(main):003:0>
···
On Wed, 24 Mar 2004 11:32:47 +0900, Harry Ohlsen wrote:
Is there an easy way to discover the path to a “require”-ed module (assuming it’s a .rb file)?
Ie, is there some way to find out where the interpreter would find fred.rb if I said
require ‘fred’
–
Simon Strandgaard
Simon Strandgaard wrote:
You may want to look at rextra… I found this
def required
result =
$".each do |file|
$:.each do |path|
if File.exists?( path + ‘/’ + file )
result << (path + ‘/’ + file)
next
end
end
end
result
end
From the output, I’m guessing $" is the list of requires that have been executed so far?
I couldn’t find that one in Ruby In A Nutshell … that’s not to say it isn’t in there, of course.
I ended up with the following, which does a couple of other things. If you give the script no arguments, it displays a list of all .rb files in the search path. For any modules after a “-e” it invokes gvim (replace by your editor of choice).
That does everything I need for now.
Thanks to both you and Assaph for the help!
···
def which(libname)
$:.each do |d|
f = File.join(d, libname)
f += “.rb”
return f if File.exists? f
end
nil
end
def list_modules
Find all the .rb files
modules = {}
$:.each do |d|
Dir[d + "/.rb"].each do |path|
base = path.sub(/.//, “”).sub(/.rb/, “”)
modules[base] = path
end
end
Display them, sorted by module name
maxWidth = 0
modules.keys.each do |mod|
length = mod.length
if length > maxWidth
maxWidth = length
end
end
modules.keys.sort.each do |mod|
printf “%-*s %s\n”, maxWidth, mod, modules[mod]
end
end
if ARGV.length == 0
list_modules
else
edit = false
ARGV.each do |mod|
if mod == “-e”
edit = true
else
if (path = which mod).nil?
puts “Can’t find module ‘#{mod}’”
else
if edit
system “gvim #{path}”
else
puts path
end
end
end
end
end
Simon Strandgaard wrote:
Is there an easy way to discover the path to a “require”-ed module (assuming it’s a .rb file)?
You may want to look at rextra… I found this
def required
result =
$".each do |file|
$:.each do |path|
if File.exists?( path + ‘/’ + file )
result << (path + ‘/’ + file)
next
end
end
end
result
end
Btw, this is not really reliable (i.e. always correct) right? Since $:
might have been manipulated in between. Also the code above did not
check the case when a file is required by absolute path.
To be more reliable, perhaps extend Kernel::require. Or always require
with absolute path (but that’s un-Rubic).
···
–
dave
David Garamond wrote:
Btw, this is not really reliable (i.e. always correct) right? Since $:
might have been manipulated in between. Also the code above did not
check the case when a file is required by absolute path.
True.
Fortunately, for my purpose, it was perfect. I was really more interested in being able to find the source code to a given library module.
Of course, given what you say, very occasionally, I won’t be looking at the right piece of code, but I can live with that :-).
Cheers,