From: dblack@...
Date: 2007-07-26T06:56:40+09:00
Subject: Re: opposite of [thing].flatten

Hi --

On Thu, 26 Jul 2007, Phlip wrote:

> Gregory Brown wrote:
>
>>>> Array([["foo"]])
>> => [["foo"]]
>>
>> It does not accidentally flatten nested arrays, and does not throw a
>> warning like Object#to_a does
>
> Ruby is a strongly-typed language that permits you to write interfaces that
> are as feebly- or strongly-typed (or statically-typed) as you like.
>
> If your interface permits one item or a series of similar items, then those
> nested arrays are not "accidentally" flattened, they are deliberately
> pushed into your interface's contract.

There are certainly cases where the flattening is not accidental, but
it sounds like those aren't the ones Greg was referring to :-)  It's
really just a question of flattening being greedy and a bit of a
"gotcha" at times.  In any case, 1.9 introduces an argument to
flatten, so one can do:

   array.flatten(1)

and not have to worry about it.


David

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