Forum: Ruby is there a way to get or list all available classes?

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8d6f5daee16e380ce0ac00395b417fb6?d=identicon&s=25 uval (Guest)
on 2005-11-30 23:56
(Received via mailing list)

topic says it all
for example irb knows many classes like Dir, File, Process, Thread ..
can I somehow list them, maybe the are kept in some array ..
if it's possible, can additional classes provided through
require "foo"
be listet too?

I hope my question is clear
thanks in advance

Regards, Daniel
D83785463666ae9bb98a0753eebc8950?d=identicon&s=25 nightphotos (Guest)
on 2005-12-01 00:04
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Hi Daniel,

Try this:

irb(main):001:0> ObjectSpace.each_object(Class) {|c| p c}

Wayne Vucenic
No Bugs Software
Ruby and C++ Agile Contract Programming in Silicon Valley
37a3c73ffbf864e4b28f7f2384ee12ce?d=identicon&s=25 Timothy Hunter (tim-hunter)
on 2005-12-01 00:52
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Daniel Schüle wrote:
> thanks in advance
> Regards, Daniel
classes = []
ObjectSpace.each_object {|obj| classes << obj if obj.class == Class}
classes = classes.sort_by {|cls| cls.inspect}
puts classes
5befe95e6648daec3dd5728cd36602d0?d=identicon&s=25 (Guest)
on 2005-12-01 11:11
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Wayne Vucenic wrote:
> OpenSSL::Digest::RIPEMD160
> Gem::StreamUI
> ..etc...etc...etc

Note, that all approaches using ObjectSpace list only classes known to
interpreter at this moment.  There might be more classes whose files
haven't been required / loaded yet.  You won't see them.  Also,
classes may be generated dynamically.

Kind regards

430ea1cba106cc65b7687d66e9df4f06?d=identicon&s=25 david (Guest)
on 2005-12-03 10:47
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A slightly more hackish solution I think that might also work with
autoloads (way too early in the morning to go and code it), is to use
#constants, eval those, select the ones that are classes, recurse,
rinse, repeat. Mind you, this is potentially a much worse resource hog
than the ObjectSpace approach.

David Vallner
97e3d8ba68b082414cc3438d15c9d6e2?d=identicon&s=25 robert.evans (Guest)
on 2005-12-05 00:08
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Not sure exactly which list of "classes available" you want, but if
you wanted to know all the classes available to the interpreter to
load, then you could conceivably iterate the directories in $:, the
load path, and look at all .rb files in them and their subdirectories
and parse them for the classes that they define.


On Nov 30, 2005, at 2:52 PM, Daniel Schüle wrote:
9dfe8c734b0f9b37a4e218425c0a2138?d=identicon&s=25 gene.tani (Guest)
on 2005-12-05 01:48
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Robert Klemme wrote:
> > Gem::ConsoleUI
>     robert

right, and immediate values are kind of important:Fixnum, Symbol,
TrueClass, FalseClass, NilClass ;-p}
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