Ruby’s Unary Operators and How to Define Their Functionality

Ruby Unary Operators

It seems dangerous to override the "!" operator, because when used in conditions (if, until, ...) the condition may not evaluate as expected... For example (in Ruby 1.9): >> str = "hey" "hey" >> puts "if condition valued to true" if (str) #(str) condition evaluated to "true" if condition valued to true nil >> puts "if condition valued to true" if (!str) #(str) condition evaluated to "false" nil ### untill here, everything was normall ### now we overload the ! operator of "str" , and see how it impacts the if conditions-evaluation: >> def str.!; swapcase; end nil >> puts "if condition valued to true" if (str) #(str) condition evaluated to "true", as before if condition valued to true nil >> puts "if condition valued to true" if (!str) #(str) condition evaluated to **"true"** ----> because of the ! overloading if condition valued to true nil It seems a very practical option ...

Full article: http://www.rubyinside.com/rubys-unary-operators-and-how-t...