Actually, it should be JRUBY_OPTS=--1.9:

$ JRUBY_OPTS=--1.9 jruby -v
jruby 1.6.0 (ruby 1.9.2 patchlevel 136) (2011-03-16 f3b6154) (Java
HotSpot(TM) Client VM 1.6.0_24) [darwin-i386-java]

/Nick

On Wed, Mar 16, 2011 at 10:43 PM, Nick Klauer <klauer / gmail.com> wrote:
> That environment variable would be RUBYOPT
>
> $ export RUBYOPT="--1.9"
>
> and then
>
> $ jruby -v
> jruby 1.6.0 (ruby 1.8.7 patchlevel 330) (2011-03-15 f3b6154) (Java
> HotSpot(TM) 64-Bit Server VM 1.6.0_24) [darwin-x86_64-java]
>
> I use it this way most of the time.       
> is that 1.9 uses 1.9's gems, so if you notice that your gem require stops
> working, you probably forgot to install the gem for 1.9.
>
> -Nick Klauer
>
>
> On Wed, Mar 16, 2011 at 19:30, Chuck Remes <cremes.devlist / mac.com> wrote:
>
>> On Mar 16, 2011, at 5:33 PM, Chuck Remes wrote:
>>
>> >
>> > On Mar 16, 2011, at 3:34 PM, Kevin wrote:
>> >
>> >> Does this release mean that it is generally safe to use 1.9 style code
>> with
>> >> Jruby?
>> >
>> > Yes.
>>
>> Let me expand on that just a bit. JRuby still defaults to the 1.8 syntax,
>> so for running 1.9 code you must pass the --1.9 command line switch when
>> starting it up. I believe there is a way to make that a default but I don't
>> know the exact details. I assume it involves setting an environment
>> parameter to contain the --1.9 command; I recommend asking on the JRuby
>> mailing list or joining the #jruby channel on irc.freenode.net and asking
>> there.
>>
>> cr
>>
>>
>>
>>
>