gistfile1.txt

% ruby187 -e 'defined?(raise::Foo)'
% jruby -e 'defined?(raise::Foo)'
% jruby --1.9 -e 'defined?(raise::Foo)'
% rbx -e 'defined?(raise::Foo)'  
% ruby -e 'defined?(raise::Foo)'
-e:1:in `<main>': unhandled exception


% ruby -e 'p defined?(raise)'     
"method"
% ruby -e 'p defined?(raise::foo)'
nil
% ruby -e 'p defined?(raise::FOO)'
-e:1:in `<main>': unhandled exception