It looks like my package, net-irc/epic5, could benefit from ruby-single.eclass as it can only build against one ruby implementation at a time. See bug #547768 comment 1. However, for my package to build against a particular implementation of ruby, it requires me to pass its configure script a command that invokes the ruby implementation to be compiled against. It looks like ruby-utils.eclass and ruby-single.eclass do not set ${RUBY}. As I was looking at porting my ebuild to ruby-single.eclass, I couldn’t figure out a “right” way find the ruby binary from the implementation provided in ${RUBY_DEPS}. I can imagine that other similar packages would be interested in being able to use ruby_get_libruby() with ruby-single.eclass too. Is my package the sort of situation that ruby-single.eclass is intended for? If so, I think ruby-single.eclass needs to provide more information about the arbitrarily chosen ruby implementation. Otherwise, I think some small changes to ruby-ng.eclass to make it friendlier to applications that can only build against a single optional ruby implementations would be great. (It already works OK for non-optional single ruby dependency, you could just put REQUIRED_USE="^^ ( $(ruby_get_use_targets) )", but for RUBY_OPTIONAL=yes… see bug #547768 comment 1).
*** This bug has been marked as a duplicate of bug 513888 ***