Re: Proposal: Array#walker

Hi --

On Wed, 14 Nov 2007, Kornelius Kalnbach wrote:

>
>
> Am 14.11.2007 um 01:37 schrieb Wolfgang N=C3=A1dasi-Donner <ed.odanow@won=
ado.de>:
>
>> Good morning all together!
>>=20
>> I know it is very late for Ruby 1.9.1 proposals, but I have a very simpl=
e=20
>> and easy suggestion. While writing a program to generate the Ruby progra=
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>> for some guessUTF test (border cases which should not success), I=20
>> recognized, that it can be very helpful for several use cases to have a=
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>> method Array#walker with the following Ruby implementation...
>>=20
>> class Array
>> def walker
>>   l =3D self.length
>>   l.times do |i|
>>     yield self[0, i], self[i], self[i+1, l-i-1]
>>   end
>> end
>> end
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>> A simple usage example is...
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>> [1,2,3,4].walker{|pre,el,post|puts "#{pre.inspect}-#{el} -=20
>> #{post.inspect}"}
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>> Output:
>> []-1 - [2, 3, 4]
>> [1]-2 - [3, 4]
>> [1, 2]-3 - [4]
>> [1, 2, 3]-4 - []
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>> What do you think about this (hopefully) minor change proposal?
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>> Wolfgang N=C3=A1dasi-Donner
>>=20
>>=20
>
> I think this is a very specialized method that should not go into the cor=
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> library...

I agree; it might be a technique you'd want to do sometimes, but I'd
put it in the category of use cases that can be addressed with what's
there already and don't need dedicated core methods of their own.


David

--=20
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