[#27003] [Bug #2422] splat operator fails on array of 1 element — Raul Parolari <redmine@...>

Bug #2422: splat operator fails on array of 1 element

12 messages 2009/12/02

[#27025] [Backport #2431] StringIO#{gets,readlines} with "" (paragraph mode) trims last "\n" — Hiroshi NAKAMURA <redmine@...>

Backport #2431: StringIO#{gets,readlines} with "" (paragraph mode) trims last "\n"

8 messages 2009/12/04

[#27086] [Feature #2454] OpenSSL has no maintainer — Yui NARUSE <redmine@...>

Feature #2454: OpenSSL has no maintainer

16 messages 2009/12/07

[#27120] #to_enum ignores block? — Roger Pack <rogerdpack@...>

Is #to_enum ignoring its block expected?

11 messages 2009/12/09

[#27135] better GC? — Roger Pack <rogerdpack@...>

Could I put in a small plea for a better GC?

56 messages 2009/12/10
[#27136] Re: better GC? — Yukihiro Matsumoto <matz@...> 2009/12/11

Hi,

[#27476] Re: better GC? — Paul Brannan <pbrannan@...> 2010/01/07

On Fri, Dec 11, 2009 at 09:07:16AM +0900, Yukihiro Matsumoto wrote:

[#27477] Re: better GC? — Eero Saynatkari <ruby-ml@...> 2010/01/07

Excerpts from Paul Brannan's message of Thu Jan 07 21:53:34 +0200 2010:

[#27563] Re: better GC? — Brent Roman <brent@...> 2010/01/12

[#27199] [Backport #2488] thread usage can result in bad HANDLE — Roger Pack <redmine@...>

Backport #2488: thread usage can result in bad HANDLE

12 messages 2009/12/16

[#27286] [Bug #2515] Array#select! — Roger Pack <redmine@...>

Bug #2515: Array#select!

17 messages 2009/12/22

[#27327] [Bug #2531] Ruby 1.8.7-p248 fails to cross-compile same version — Luis Lavena <redmine@...>

Bug #2531: Ruby 1.8.7-p248 fails to cross-compile same version

9 messages 2009/12/25

[#27360] [Feature #2542] URI lib should be updated to RFC 39886 — Marc-Andre Lafortune <redmine@...>

Feature #2542: URI lib should be updated to RFC 39886

15 messages 2009/12/31

[ruby-core:27271] [Bug #2422] splat operator fails on array of 1 element

From: katz bo <redmine@...>
Date: 2009-12-21 16:02:33 UTC
List: ruby-core #27271
Issue #2422 has been updated by katz bo.


Thank you, Benoit Daloze.

I wrote:
> What does Ruby do with a = *[] ? Let me illustrate an IMO proper way:
> Ruby looks at *[] and goes, "Fine, let me unpack it."
> Ruby unpacks *[].
> Then Ruby goes, "Nothing? But I can't _carry_ <nothing>! No.. not in an
> assignment! Wait.. Let's do it!"
> Ruby marks it as nil.

As now I think I understand assignment better, I'd like to correct myself a bit:

foo = *[]
When processing the above line, the Ruby interpreter does these things:
1) First Ruby sees the left side of the assignment, i.e. foo =, and he points foo to nil.
2) Then Ruby tries to evaluate the rvalue. Looking at the *, Ruby unpacks the array [].
3) Ruby gets a little surprised when he finds it's empty in there.
4) So Ruby (happily) does nothing, because there is nothing to re-point foo to.

That's the story. And this story tells me foo ends up nil.
What's the new story about ruby 1.9 if it's not a bug?
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