From: Love U Ruby <lists@...>
Date: 2013-02-27T05:48:30+09:00
Subject: Re: Confusion with self within methods.

Here is the answer:

Would feel great if anyone helped me here to understand the topic. But 
anyway not encouraging other's talk myself produced the answer for 
future comers.

We all know that - ***`self inside a method is always the object on 
which the method was called`***. So let's try and examine the 
truthfulness of that.


Let's see who is default `self` from the below code first of all:

    m=self
    # => main
    m.class
    # => Object

Okay, the default `self` is the object of `Object` class.

Just written the below code in more simplified way, from the description 
mentioned code,to highlight on the concept.

    def test
    p self.class
    def show
    p self.class
    end
    end
    # => nil

Keeping in mind `self inside a method is always the object on which the 
method was called` called only `test` as below.

    test
    Object
    # => nil

Yes, `Object` has been returned,on which the `test` has been called,that 
means the above statement is true.

    test.show
    Object
    NilClass
    # => NilClass

Calling to `test` also returns `nil` due to the block `def show;p 
self.class;end`.Now `nil` is an object of `NilClass`. Thus `show` method 
has been called on `NilClass` object. As result `self` is `NilClass`. 
Again the above statement holds.

With the above concept trying to reach to the actual goal with tiny 
steps:

    def test
    p "1. # => #{self}"
    def show
    p "2. # => #{self}"
    end
    end
    # => nil

    test
    "1. # => main" #<~~ main is an object of class Object,on which test 
was called from IRB.
    # => nil

    test.show
    "1. # => main"
    "2. # => "    #<~~ nil("" means nil.to_s) is an object of 
Nilclass,on which show was called from IRB.
    # => "2. # => "

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