[#14696] Inconsistency in rescuability of "return" — Charles Oliver Nutter <charles.nutter@...>

Why can you not rescue return, break, etc when they are within

21 messages 2008/01/02
[#14699] Re: Inconsistency in rescuability of "return" — Gary Wright <gwtmp01@...> 2008/01/02

[#14738] Enumerable#zip Needs Love — James Gray <james@...>

The community has been building a Ruby 1.9 compatibility tip list on

15 messages 2008/01/03
[#14755] Re: Enumerable#zip Needs Love — Martin Duerst <duerst@...> 2008/01/04

Hello James,

[#14772] Manual Memory Management — Pramukta Kumar <prak@...>

I was thinking it would be nice to be able to free large objects at

36 messages 2008/01/04
[#14788] Re: Manual Memory Management — Marcin Raczkowski <mailing.mr@...> 2008/01/05

I would only like to add that RMgick for example provides free method to

[#14824] Re: Manual Memory Management — MenTaLguY <mental@...> 2008/01/07

On Sat, 5 Jan 2008 15:49:30 +0900, Marcin Raczkowski <mailing.mr@gmail.com> wrote:

[#14825] Re: Manual Memory Management — "Evan Weaver" <evan@...> 2008/01/07

Python supports 'del reference', which decrements the reference

[#14838] Re: Manual Memory Management — Marcin Raczkowski <mailing.mr@...> 2008/01/08

Evan Weaver wrote:

[#14911] Draft of some pages about encoding in Ruby 1.9 — Dave Thomas <dave@...>

Folks:

24 messages 2008/01/10

[#14976] nil encoding as synonym for binary encoding — David Flanagan <david@...>

The following just appeared in the ChangeLog

37 messages 2008/01/11
[#14977] Re: nil encoding as synonym for binary encoding — Yukihiro Matsumoto <matz@...> 2008/01/11

Hi,

[#14978] Re: nil encoding as synonym for binary encoding — Dave Thomas <dave@...> 2008/01/11

[#14979] Re: nil encoding as synonym for binary encoding — David Flanagan <david@...> 2008/01/11

Dave Thomas wrote:

[#14993] Re: nil encoding as synonym for binary encoding — Dave Thomas <dave@...> 2008/01/11

[#14980] Re: nil encoding as synonym for binary encoding — Gary Wright <gwtmp01@...> 2008/01/11

[#14981] Re: nil encoding as synonym for binary encoding — Yukihiro Matsumoto <matz@...> 2008/01/11

Hi,

[#14995] Re: nil encoding as synonym for binary encoding — David Flanagan <david@...> 2008/01/11

Yukihiro Matsumoto writes:

[#15050] how to "borrow" the RDoc::RubyParser and HTMLGenerator — Phlip <phlip2005@...>

Core Rubies:

17 messages 2008/01/13
[#15060] Re: how to "borrow" the RDoc::RubyParser and HTMLGenerator — Eric Hodel <drbrain@...7.net> 2008/01/14

On Jan 13, 2008, at 08:54 AM, Phlip wrote:

[#15062] Re: how to "borrow" the RDoc::RubyParser and HTMLGenerator — Phlip <phlip2005@...> 2008/01/14

Eric Hodel wrote:

[#15073] Re: how to "borrow" the RDoc::RubyParser and HTMLGenerator — Eric Hodel <drbrain@...7.net> 2008/01/14

On Jan 13, 2008, at 20:35 PM, Phlip wrote:

[#15185] Friendlier methods to compare two Time objects — "Jim Cropcho" <jim.cropcho@...>

Hello,

10 messages 2008/01/22

[#15194] Can large scale projects be successful implemented around a dynamic programming language? — Jordi <mumismo@...>

A good article I have found (may have been linked by slashdot, don't know)

8 messages 2008/01/24

[#15248] Symbol#empty? ? — "David A. Black" <dblack@...>

Hi --

24 messages 2008/01/28
[#15250] Re: Symbol#empty? ? — Yukihiro Matsumoto <matz@...> 2008/01/28

Hi,

Re: Inconsistency in rescuability of "return"

From: Charles Oliver Nutter <charles.nutter@...>
Date: 2008-01-03 09:55:48 UTC
List: ruby-core #14722
Gary Wright wrote:
> So in 1.9 eval is creating a 'stronger' scope than in 1.8 and hiding the 
> loop/iterator context from the code in the string that is being 
> evaluated.  In this new, more private, context a bare break is always a 
> syntax error.  It doesn't matter where the eval is taking place.

And I prefer the 1.9 behavior, since it doesn't require that eval'ed 
code be able to "see" outside itself to know how to handle things like 
break or next.

> I'm not sure I understand you second point above. If you catch the 
> syntax error with a rescue clause within the loop, then the loop won't 
> be terminated.  If you don't catch the error then the loop will be 
> terminated.  But this is just the normal behavior of any sort of 
> exception--there is nothing special about 'break' in this case--any old 
> syntax error would do the same thing.

Not true; try it yourself, it's not a "normal" exception that terminates 
the loop and bubbles out, it's a "special" exception that ends the loop 
as though a normal "break" were called. So basically, either the 
non-exception or exception-based "break" can quietly terminate a loop, 
but only one is catchable.

> It seems like the 1.9 behavior is more consistent with the fact that 
> eval does create a new scope of sorts. The fact that the iterator 
> context leaked into the 1.8 eval string scope seems more like a bug than 
> a feature.

Agreed. Even without the 1.9 SyntaxError (which requires more parser 
smarts) it seems like 1.8 should cause a bare 'break' or 'return' or 
'next' or friends to always raise a LocalJumpError in every cases, even 
when the eval itself is within a loop. That would at least be 
consistent, even if it's a little goofy that e.g. a 'break' 
LocalJumpError can quietly terminate a loop.

- Charlie

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