On Tuesday 29 December 2009 07:25:13 am Aldric Giacomoni wrote:
> I suggest Gentoo: it has a tool
> available to switch painlessly between Ruby 1.8 and 1.9, which allows
> for any and all setup on editors and such to be simple and just link to
> #!/usr/bin/ruby ... For instance.

That would imply you can't have both 1.8 and 1.9 programs running 
simultaneously. Ubuntu installs 1.9 as /usr/bin/ruby1.9.

Also, most programs that are actually meant to run standalone will have 
#!/usr/bin/env ruby, which means you can simply change your path to switch 
interpreters.