[#385051] How to order Structs based on two fields — Iñaki Baz Castillo <ibc@...>

Hi, I've a struct like this:

20 messages 2011/07/01
[#385052] Re: How to order Structs based on two fields — Iñaki Baz Castillo <ibc@...> 2011/07/01

2011/7/1 I=C3=B1aki Baz Castillo <ibc@aliax.net>:

[#385057] Re: How to order Structs based on two fields — Robert Klemme <shortcutter@...> 2011/07/01

On Fri, Jul 1, 2011 at 12:55 PM, I=F1aki Baz Castillo <ibc@aliax.net> wrote=

[#385069] Offering Help — Joe Peric <peric.joe@...>

I'm new to Ruby and I am willing to learn. Anyone need help on a

18 messages 2011/07/01
[#385072] Re: Offering Help — Jeremy Heiler <jeremyheiler@...> 2011/07/01

On Fri, Jul 1, 2011 at 11:43 AM, Joe Peric <peric.joe@gmail.com> wrote:

[#385073] Re: Offering Help — Joe Peric <peric.joe@...> 2011/07/01

Never heard of it, but I'll get right on it. Thanks.

[#385082] Re: Offering Help — Joe Peric <peric.joe@...> 2011/07/02

Just finished this. I had to find some more info on exceptions to get

[#385083] Re: Offering Help — Jeremy Heiler <jeremyheiler@...> 2011/07/02

On Sat, Jul 2, 2011 at 1:39 PM, Joe Peric <peric.joe@gmail.com> wrote:

[#385102] symbol vs string for hash keys — Intransition <transfire@...>

What are the important factors to consider when deciding whether to

12 messages 2011/07/03

[#385160] Fatal Error with Ruby/GTK2, Homebrew, Green Shoes, and OSX Snow Leopard — Timothy Barnes <barnes7td@...>

I posted the below question to the Shoes mailing list and got back the

10 messages 2011/07/09

[#385194] RubyInstaller Extras — Jon <jon.forums@...>

Since 2009, we've been pleased to include Huw Collingbourne's The Book of Ruby with RubyInstaller. Well now, Huw has a newly updated version, and he's published it with No Starch Press.

11 messages 2011/07/12

[#385207] Creating a range of directories — Simon Harrison <simon@...>

I'm wanting to create a range of directories with a prefix, like the

13 messages 2011/07/13

[#385276] Is there a more efficient way to remove data from a string? — Eddie Catflap <catflaporama@...>

Hi

9 messages 2011/07/15

[#385297] Help needed for a new release of text-hyphen — Austin Ziegler <halostatue@...>

I've had folks asking me for a release of text-hyphen that works with

12 messages 2011/07/15

[#385326] Comparing hashes based on their keys — Stefano Mioli <stefano.mioli@...>

Hi list,

13 messages 2011/07/15

[#385342] moving a 1.8.6 install? — Roggie Boone <rogboone@...>

Is it possible to move the gems from a Ruby 1.8.6 install on an (old)

10 messages 2011/07/15

[#385410] Better name for #zip_with — Intransition <transfire@...>

Any ideas for a better name for:

13 messages 2011/07/18

[#385452] Ruby + USB + CCTV Camera Driver? — "Bob Carpenter." <rgc3679@...>

I want to write a Ruby driver that handles the feed from A CCTV camera.

23 messages 2011/07/18
[#385459] Re: Ruby + USB + CCTV Camera Driver? — William Rutiser <wruyahoo05@...> 2011/07/18

On 2011-07-18 1:00 PM, Bob Carpenter. wrote:

[#385461] Re: Ruby + USB + CCTV Camera Driver? — "Bob Carpenter." <rgc3679@...> 2011/07/18

William Rutiser wrote in post #1011466:

[#385462] Re: Ruby + USB + CCTV Camera Driver? — Hassan Schroeder <hassan.schroeder@...> 2011/07/18

On Mon, Jul 18, 2011 at 11:51 AM, Bob Carpenter. <rgc3679@yahoo.com> wrote:

[#385464] Re: Ruby + USB + CCTV Camera Driver? — "Bob Carpenter." <rgc3679@...> 2011/07/18

Hassan Schroeder wrote in post #1011472:

[#385471] Re: Ruby + USB + CCTV Camera Driver? — Hassan Schroeder <hassan.schroeder@...> 2011/07/18

On Mon, Jul 18, 2011 at 12:58 PM, Bob Carpenter. <rgc3679@yahoo.com> wrote:

[#385474] Re: Ruby + USB + CCTV Camera Driver? — Phillip Gawlowski <cmdjackryan@...> 2011/07/18

On Tue, Jul 19, 2011 at 12:18 AM, Hassan Schroeder

[#385477] Re: Ruby + USB + CCTV Camera Driver? — "Bob Carpenter." <rgc3679@...> 2011/07/19

Phillip Gawlowski wrote in post #1011503:

[#385509] A beginner question. — "Cajus A." <cajus_@...>

Hi i'm trying to write and example program where you speak to a

12 messages 2011/07/19

[#385542] Splitting strings — Ryan Mckenzie <ryan@...>

Hi all,

18 messages 2011/07/19

[#385565] error building ruby p290 — Dev Guy <devguy.ca@...>

I get the following build error on my Linux box while trying to build

12 messages 2011/07/20

[#385629] Are Job Ads OK? — Lee Hughes <lee@...>

Is it OK to post Ruby job ads on this forum?

12 messages 2011/07/21

[#385847] String manuplation example — kotin 76 <kotin76@...>

Hi,

15 messages 2011/07/27

[#385860] Counting lines of code in a ruby code file ignoring method code lines in the process — Harry Truax <htruax@...>

Hello,

8 messages 2011/07/27

[#385936] Help in Pointer — Tridib Bandopadhyay <tridib04@...>

Hello

18 messages 2011/07/29

[#386012] Ruby a "4th generation language"? Credible sources? — Albert Schlef <albertschlef@...>

I've noticed that Wikipedia says that "C#, Java" are 3'rd generation

13 messages 2011/07/31

[#386050] system stack error in ObjectSpace.each_object — luke gruber <luke.gru@...>

Hey guys, I'm just starting to mess around with metaprogramming in Ruby,

14 messages 2011/07/31
[#386052] Re: system stack error in ObjectSpace.each_object — Josh Cheek <josh.cheek@...> 2011/07/31

On Sun, Jul 31, 2011 at 4:29 PM, luke gruber <luke.gru@gmail.com> wrote:

[#386055] Re: system stack error in ObjectSpace.each_object — luke gruber <luke.gru@...> 2011/08/01

> Typically, SystemStackError is due to recursing for too long, perhaps I

[#386058] Re: system stack error in ObjectSpace.each_object — Robert Klemme <shortcutter@...> 2011/08/01

On Mon, Aug 1, 2011 at 3:56 AM, luke gruber <luke.gru@gmail.com> wrote:

Re: Why return(XXX) is valid within a "value = case N ..." ?

From: Robert Klemme <shortcutter@...>
Date: 2011-07-14 09:13:50 UTC
List: ruby-talk #385248
On Thu, Jul 14, 2011 at 10:56 AM, I=F1aki Baz Castillo <ibc@aliax.net> wrot=
e:
> Hi, the following code does not "compile":
>
> -----------------------------
> =A0def test1
> =A0 =A0value =3D return("lalala")
> =A0end
> -----------------------------
> =3D> SyntaxError: (irb):11: void value expression
>
>
> Ok, it makes sense. So then, why the following does not fail?
>
> -----------------------------
> =A0def test2
> =A0 =A0value =3D case 123
> =A0 =A0 =A0when Fixnum
> =A0 =A0 =A0 =A0return "returning 'Fixnum' string from method test2"
> =A0 =A0 =A0end
> =A0 =A0puts "method test2 ends now"
> =A0end
> --------------------------
> irb> test2
> =3D> "returning 'Fixnum' string from method kk"

Probably because case has branches which actually return a value (even
if it is fall through and nil).  Interestingly enough this does not
work with if:

11:07:59 ~$ ruby19 -c x.rb
x.rb:7: void value expression
11:08:04 ~$ cat -n x.rb
     1
     2  def a
     3    x =3D if rand(10) =3D=3D 0
     4      99
     5      else
     6      return 55
     7      end
     8  end
11:08:07 ~$

Could be that you have found a loophole in the parser logic. :-)

> I'm using Ruby 1.9.2 and in fact I use a method like "test2" it in my
> project, but it seems a bit strange for me and I would like to be sure
> that it's something correct (even if IMHO it does not make sense) and
> will not change in a future Ruby 1.9 version.

I'd say stop using this idiom.  If you use a "case" expression because
it should yield a value (i.e. "x =3D case...end") then I would only use
exceptions as other way out.  A "return" indicates regular execution
flow which in the case of this usage of "case" would mean "have case
return a value" but not "return from the method".

If you use "case" as a control flow construct (i.e. without assigning
the result) then a "return" inside is OK and Ruby will also accept it.
 Same goes for "if".

Kind regards

robert

--=20
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

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