Tutorial by Examples

Many languages feature a with statement that allows programmers to omit the receiver of method calls. with can be easily emulated in Ruby using instance_eval: def with(object, &block) object.instance_eval &block end The with method can be used to seamlessly execute methods on object...

With Ruby you can modify the structure of the program in execution time. One way to do it, is by defining methods dynamically using the method method_missing. Let's say that we want to be able to test if a number is greater than other number with the syntax 777.is_greater_than_123?. # open Numeric...

In ruby you can add methods to existing instances of any class. This allows you to add behavior to and instance of a class without changing the behavior of the rest of the instances of that class. class Example def method1(foo) puts foo end end #defines method2 on object exp exp = E...

send() is used to pass message to object. send() is an instance method of the Object class. The first argument in send() is the message that you're sending to the object - that is, the name of a method. It could be string or symbol but symbols are preferred. Then arguments those need to pass in met...