Doubts on methods of Method Class in ruby

Question

I have read http://www.ruby-doc.org/core-2.1.1/Method.html . I have some doubts on methods of Method class:

1. What is the difference between name and original_name ?
2. Would source_loction give nil for ruby gem related Method objects?
3. I have seen the receiver would give the bound receiver of method object. What is the meaning of bound receiver?

Is there anyway to distinguish between the method created by def <method_name> ..... end and define_method(symbol){block} ?

Answer 1

1. What is the difference between name and original_name ?

   original_name returns the original name for aliased methods :

    def foo; end alias bar foo method(:bar).name #=> :bar method(:bar).original_name #=> :foo 

2. Would source_loction give nil for ruby gem related Method objects?

   source_location works for gems, too:

    require 'rails' Rails.method(:version).source_location #=> [".../ruby/2.1.1/gems/railties-4.1.0/lib/rails/version.rb", 5] 

   It returns nil for native methods, ie methods written in C:

    method(:puts).source_location #=> nil 

3. I have seen the receiver would give the bound receiver of method object. What is the meaning of bound receiver?

   Bound methods are associated with a particular object (the receiver) and can be called, eg:

    str = "abc" str.method(:upcase) #=> #<Method: String#upcase> 

   instance_method returns the method as an unbound method:

    String.instance_method(:upcase) #=> #<UnboundMethod: String#upcase> 

   UnboundMethod doesn't have a receiver and can't be called (there's no string instance you could upcase).

4. Is there anyway to distinguish between the method created by def <method_name> ..... end and define_method(symbol){block} ?

   I don't think so.