From: Ryan Davis <ryand-ruby@...>
Date: 2009-02-27T04:34:04+09:00
Subject: Re: "def nothing=(data) false end" returns 'data' instead of 'false'


On Feb 26, 2009, at 07:09 , Ken Bloom wrote:

> Because when you use test.nothing=123, you're not directly calling the
> method -- you're acutally doing an assignment operator, which calls  
> the
> nothing= internally. The assignment operator always returns the  
> value on
> the right side, and the return value from nothing= is ignored.


to go one level deeper on Ken's explanation:

> % echo "attr_accessor :x; self.x = 42" | parse_tree_show
> s(:block,
>  s(:call, nil, :attr_accessor, s(:arglist, s(:lit, :x))),
>  s(:attrasgn, s(:self), :x=, s(:arglist, s(:lit, 42))))

the attrasgn node does the call and returns the value of the arglist  
regardless of the call's return value(s).