From: dblack@...
Date: 2007-05-11T06:45:58+09:00
Subject: Re: self in blocks

Hi --

On Fri, 11 May 2007, Vasco Andrade e silva wrote:

> Hi
>
> This seems to me somehow inconsistent:
>
> class A; end
>
> # 1)
> # output A
> A.class_eval { puts self }
>
> # 2)
> # output main (in irb)
> [1].each { puts self }
>
> The "problem" to me is that in 1) 'self' seems to refer to the context
> where yield is called, where in 2) seems to refer to the context in
> execution.
> What should i expect from 'self'`s behaviour?

self doesn't really behave; it just plays the role it's assigned to
play in different circumstances.  class_eval sets self to the
receiver (it's specially designed for that purpose -- basically a
programmatic rather than declarative way to enter a class definition
block).  In general, though, self doesn't change when you enter a
code block.  That's why self is still main inside your second block.


David

-- 
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