From: George Ogata Date: 2006-02-20T23:33:30+09:00 Subject: Re: [/QUIZ] metakoans.rb (#67) "Sander Land" writes: >> On 2/19/06, George Ogata wrote: >> ... >> define_method("#{arg}?"){|| !send(arg).nil?} >> ... > what about send(arg) == false ? Good point! The koans didn't question that, though. Indeed, `!!send(arg)' is a better solution. So is using `defined?' instead of `instance_variables.include?'.