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There doesn't seem to be any ri documentation on core ruby classes on my system. Using ri -c I see that there are docs for a few gems I've installed, but that's it.

$ ri Array
Nothing known about Array

I'm using the standard system ruby1.8 ( I'm not using rvm. Is there some other package I need to install? On a very similar machine (also Oneiric with ruby 1.8) ri Array works just fine, and I can't tell what the difference is.

ruby -v on the problematic machine:

ruby 1.8.7 (2011-06-30 patchlevel 352) [i686-linux]

and on the normal machine:

ruby 1.8.7 (2011-06-30 patchlevel 352) [x86_64-linux]
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Can you add the full output of ruby -v on both machines to your question? Thanks. – James Feb 11 '12 at 13:30
up vote 0 down vote accepted

Lo and behold, there is a package. In my defense, there are so many hits for aptitude search ri that I didn't see it.

apt-get install ri1.8
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