From: "David A. Black" <dblack@...>
Date: 2009-02-26T21:56:23+09:00
Subject: Re: Where is splat implemented? / How does it work?

Hi --

Mischa Fierer wrote:
> Thanks for all the replies.
>
> I've taken a lot of the stuff here, plus all the examples I could find
> for the splat, and written what I think is probably the most definitive
> guide at this point. You can run it yourself, as well, which should be
> useful.
>
> Some of the examples are from a post David Black made a year or so ago,
> others are from Rick and matz.
>
> http://github.com/mischa/splat/tree/master
>
> I've also written it so that you can try to guess what the return value
> will be.
>
> Please do let me know if anything is wrong with it, also feel free to
> fork and add your own examples / tests.

Note this change, between 1.8 and 1.9:

1.8:

 >> *a = [1,2,3]
=> [[1, 2, 3]]
 >> a
=> [[1, 2, 3]]

1.9:

 >> *a = [1,2,3]
=> [1, 2, 3]
 >> a
=> [1, 2, 3]

I think this means that my "that which, when wrapped in an array" 
formula doesn't work for this case any more -- though that formula was 
my best shot at a pithy way of describing the star, and may be outdated 
and/or incomplete in other ways. (I can't think of any, but someone else 
might :-)

That's why I've always called this the "unary unarray" operator.


David

-- 
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