From: jeffz_2002@...
Date: 2007-01-04T03:05:07+09:00
Subject: Re: Pickaxe question: "... on the way to true Ruby mastery."

Thanks David and Andre, I finally get it, and Andre, you're right about
the nil/false idea in your response to my reponse.

For anyone else following this thread, the idea is:

- The first time the method is called, @foo doesn't exist.

- @foo doesn't exist, so it's assigned a single-element array
containing the value returned by the call to the private aliased
original method.  This value can be anything, including an array,
false, nil, whatever.

- The 0th array element, which is just the return value of the function
call, is returned.

- The next time the method is called, @foo still exists, and is still a
single-element array.  We again return the 0th element, which is the
answer.

The [0] is used because the result is stored in an array ... this gets
around the original method returning nil or false, which would end up
in a second call to the function, had we just naively used @foo ||=
foo( *args, &block )..

Thanks again.  It's pretty obvious, actually ... sigh.

Funny, I still don't feel well on my way to mastery.  I actually feel
dumber, in a way.

jz