gauss:tools brian$ ruby -d -e 'p $DEBUG'
true
gauss:tools brian$ ruby -d -e 'p \$DEBUG'
-e:1: syntax error, unexpected $undefined, expecting $end
p \$DEBUG
   ^
gauss:tools brian$ ruby -d -e 'p $DEBUG'
true
gauss:tools brian$ jruby -d -e 'p $DEBUG'
gauss:tools brian$ jruby -d -e 'p \$DEBUG'
gauss:tools brian$ ruby -v
ruby 1.8.6 (2008-03-03 patchlevel 114) [universal-darwin9.0]
gauss:tools brian$ jruby -v
jruby 1.2.0 (ruby 1.8.6 patchlevel 287) (2009-02-08 rev 9070) [i386-java]