From: matt@... (matt neuburg)
Date: 2006-12-08T02:20:05+09:00
Subject: Re: Array changing after concat function

WKC CCC <wai-kee.chung@uk.bnpparibas.com> wrote:

> Can someone shed some light on this problem. In the example, I am
> attempting to concatenate two arrays together. However it appears that
> the contents of the first array is being altered after using the concat
> function even though a copy of the array is being used. Am I doing
> something wrong here, or is this a potential bug?
> 
> Thanks
> 
> one = [[1],[2]]
> two = [['a'],['b']]
> 
> puts one.inspect
> 
> newArray =[]
> count = 0
> 
> tempArr = Array.new(one)
> 
> tempArr.each do |x|
>   x = x.concat(two.values_at(count))
>   newArray = newArray.push(x)
>   count = count + 1
> end
> 
> puts one.inspect

Array.new(array) copies the *array* but it does not copy its *elements*.
So tempArr[0] is another name for the very same object as one[0], and so
forth. m.

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