The Well-Grounded Rubyist, Second Edition

4.3. The method_missing method

The Kernel module provides an instance method called method_missing. This method is executed whenever an object receives a message that it doesn’t know how to respond to—that is, a message that doesn’t match a method anywhere in the object’s method-lookup path:

>> o = Object.new
=> #<Object:0x0000010141bbb0>
>> o.blah
NoMethodError: undefined method `blah' for #<Object:0x0000010141bbb0>

It’s easy to intercept calls to missing methods. You override method_missing, either on a singleton basis for the object you’re calling the method on, or in the object’s class or one of that class’s ancestors:

When you override