[ruby-core:94771] [Ruby master Feature#16141] Change in the array[x, y] notation.

Issue #16141 has been updated by matz (Yukihiro Matsumoto).

Status changed from Open to Closed

The `y` in `ary[x, y]` means the length of resulting subarray, not an index. There's no subarray of negative length.

Matz.


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Feature #16141: Change in the array[x,y] notation.
https://bugs.ruby-lang.org/issues/16141#change-81382

* Author: professeurx (Fran輟ys Proulx)
* Status: Closed
* Priority: Normal
* Assignee: 
* Target version: 
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It not a bug, but it's an oddity of the language.

``` ruby
array_four  = %w[a b c d e f g] 

p array_four[1,3]  
p array_four[-1,3]  
p array_four[3,3] 
p array_four[-3,2] 
p array_four[-3, -2] 

["b", "c", "d"]
["g"]
["d", "e", "f"]
["e", "f"]
nil

```
p array_four[-3, -2]  do not follow the principal of the least surprise!
the logical output would be ["d", "e"]

The way i see this
p array_four[-3,2] # take 3 step from the end and take 2 elements incrementally 

and
p array_four[-3,-2] # take 3 step from the end and take 2 elements decrementally

The change wouldn't affect the retro-compatibility of the language.





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