From: alxtskrnk@...
Date: 2015-02-10T16:23:51+00:00
Subject: [ruby-core:68082] [Ruby trunk - Bug #10837] spatting a single element array produces an array instead of a single value for return and next

Issue #10837 has been updated by bug hit.


Marc-Andre Lafortune wrote:
> bug hit wrote:
> > `b = *[a]` is `b = [a]` why?
> > `(next|return) *[a]` is `(next|return) [a]` why?
> 
> I agree, this can be surprising.
> 
> The reason for the behavior is that `return 1, 2`, strictly speaking, shouldn't be valid Ruby as you can only return one value. Instead of forbidding it, `return 1, 2` is automatically converted to `return [1, 2]`. They are equivalent. So `return *array` is converted to `return [*array]`, and that holds even in the cases where `array` contains one or no element (or isn't an array).
> 
> The same can be said for `next` and `=`.
> 
> HTH

So it seems it's an implementation artifact.  Would it not be better if semantics of splatting were consistent, i.e. rvalue splat would always destructure the array?

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Bug #10837: spatting a single element array produces an array instead of a single value for return and next
https://bugs.ruby-lang.org/issues/10837#change-51465

* Author: bug hit
* Status: Rejected
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-linux]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
irb(main):013:0> ->{return *[1]}.()
=> [1]
irb(main):014:0> ->{next *[1]}.()
=> [1]
______________

*[x] should mean x as it already does for arguments 



-- 
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