From: "Jan E." Date: 2012-06-13T21:47:52+09:00 Subject: Re: What's different about defind class method? bill gate wrote in post #1064388: > Why lot of Rails snippet code use __FILE__ __LINE__ __FILE__ and __LINE__ are magic constants. They point to the file/line they're in. In combination with class_eval these constants can be used to produce exact error messages. If you don't use them, an error message within the class_eval will only display the file and line of the "class_eval" (rather than the file and line of the actual string). See http://ruby-doc.org/core-1.9.3/Module.html#method-i-class_eval -- Posted via http://www.ruby-forum.com/.