From: Robert Klemme <shortcutter@...>
Date: 2009-04-20T01:10:13+09:00
Subject: Re: ruby1.9 and the retry keyword

On 19.04.2009 16:20, Yoann Guillot wrote:

> It seems that the 'retry' keyword is not supported anymore in ruby1.9 to
> restart a running iteration from the beginning.

This cannot be, "retry" works in 1.9.1:

[robert@ora01 ~]$ irb19
irb(main):001:0> i = 5
=> 5
irb(main):002:0> begin
irb(main):003:1* puts i
irb(main):004:1> raise "foo"
irb(main):005:1> rescue Exception
irb(main):006:1> i -= 1
irb(main):007:1> retry if i > 0
irb(main):008:1> end
5
4
3
2
1
=> nil
irb(main):009:0> RUBY_VERSION
=> "1.9.1"
irb(main):010:0>

> Is there a way to achieve the old behavior, preferably in a 1.8 compatible
> way ?
> 
> $ ruby1.8 -ve '[1, 2].each { puts "bla" ; retry }'
> ruby 1.8.7 (2008-08-11 patchlevel 72) [i486-linux]
> bla
> bla
> bla
> ^C

"retry" without "rescue" seems pointless to me.  As far as I can see 
"retry"'s main purpose is repetition in case of exceptions.  The use 
that you demonstrate looks like a untypical and probably unwanted idiom 
which accidentally happened to work in 1.8.* to me.

> $ ruby1.9 -ve '[1, 2].each { puts "bla" ; retry }'
> ruby 1.9.2dev (2009-04-19) [i686-linux]
> -e:1: Invalid retry
> -e: compile error (SyntaxError)

Apparently the _syntax_ was changed to allow "retry" only in "rescue" 
clauses - which makes perfectly sense for me.  I am not the definitive 
source but to me it looks like 1.9 fixes a misbehavior of 1.8 - if 
that's the case I would not want to reintroduce this just to make 1.9 
more compatible to 1.8.  In fact, 1.9 purposefully *does* have some 
incompatibilities.

Kind regards

	robert