Proposed F19 Feature: JRuby 1.7 - JRuby is an alternative Ruby implementation

[Bill Nottingham]

Bohuslav Kabrda (bkabrda at redhat.com) said: 
> JRuby and Ruby won't share extensions. Extensions for Ruby will live in %{_libdir}/gems/ruby, while extensions for JRuby will in %{_datadir}/gems/jruby (although we decided not to actually ship any JRuby extension Gems for F19 as we want to take more time to figure out the guidelines specifics around it).
> JRuby is pretty incompatible with C extensions. In fact, guys from upstream told me that they may even completely drop support for C extensions, as its very hard to maintain and doesn't really bring significant benefits. That's why we don't want to do it in Fedora.

So, thinking of this in terms of python (sorry, that's my experience), this
is the equivalent of an alternate python interpreter that can only use
.noarch python extensions/modules that don't depend on any archful python
modules?

How is an application author supposed to know which interpreter they can
use - do they have to recursively traverse their dependency stack first
before making a decision?

Bill