Sam, Tuesday, March 6, 2012, 12:09:45 PM, you wrote: SD> On 07/03/12 07:15, Robert Klemme wrote: >> You do not want the class but rather the kind of "foo". "local >> variable" is not a class. You can do >> >> irb(main):032:0> class Bogey< Dance >> irb(main):033:1> def bar >> irb(main):034:2> a=0 >> irb(main):035:2> printf "foo -> %p\n", defined?(foo) >> irb(main):036:2> printf "a -> %p\n", defined?(a) >> irb(main):037:2> printf "none -> %p\n", defined?(none) >> irb(main):038:2> end >> irb(main):039:1> end >> => nil >> irb(main):040:0> Bogey.new.bar >> foo -> "method" >> a -> "local-variable" >> none -> nil >> => nil SD> Great answer. I'm pretty new to Ruby and assumed that defined? returned SD> a boolean. That'll learn me for not reading the manual. SD> Sam Indeed, it is a great answer. Thanks Robert! Now where in online documentation can I find where "defined?" is documented? I see it explained on page 137 of the Pickaxe book but is there more formal documentation online? Also ... I find it interesting that I get a syntax error when I do defined? defined?