[#393012] Basic Ruby performance — Dmitry Nikiforov <dniq@...>

Hello all!

43 messages 2012/02/02
[#393013] Re: Basic Ruby performance — Dmitry Nikiforov <dniq@...> 2012/02/02

Here's another example with significantly bigger performance difference:

[#393015] Re: Basic Ruby performance — Ryan Davis <ryand-ruby@...> 2012/02/02

[#393016] Re: Basic Ruby performance — Peter Vandenabeele <peter@...> 2012/02/02

On Fri, Feb 3, 2012 at 12:20 AM, Ryan Davis <ryand-ruby@zenspider.com>wrote:

[#393020] Re: Basic Ruby performance — Ryan Davis <ryand-ruby@...> 2012/02/03

[#393076] Problem migrating to Ruby 1.9.2 — Patrick Bayford <pbayford@...>

Some assistance please - I have a Ruby project, which I started in Ruby

10 messages 2012/02/03

[#393164] Using _ like in Scala? — Marc Heiler <shevegen@...>

fruits = %w( apple banana orange )

27 messages 2012/02/06
[#393201] Re: Using _ like in Scala? — Tony Arcieri <tony.arcieri@...> 2012/02/07

On Mon, Feb 6, 2012 at 10:54 AM, Marc Heiler <shevegen@linuxmail.org> wrote:

[#393204] Re: Using _ like in Scala? — Eric Christopherson <echristopherson@...> 2012/02/07

On Mon, Feb 6, 2012 at 7:21 PM, Tony Arcieri <tony.arcieri@gmail.com> wrote:

[#393206] Re: Using _ like in Scala? — Tony Arcieri <tony.arcieri@...> 2012/02/07

On Mon, Feb 6, 2012 at 5:56 PM, Eric Christopherson <

[#393208] Re: Using _ like in Scala? — Kevin <darkintent@...> 2012/02/07

On Mon, Feb 6, 2012 at 9:07 PM, Tony Arcieri <tony.arcieri@gmail.com> wrote:

[#393216] Re: Using _ like in Scala? — Robert Klemme <shortcutter@...> 2012/02/07

On Tue, Feb 7, 2012 at 6:56 AM, Kevin <darkintent@gmail.com> wrote:

[#393219] Re: Using _ like in Scala? — Josh Cheek <josh.cheek@...> 2012/02/07

On Tue, Feb 7, 2012 at 4:47 AM, Robert Klemme <shortcutter@googlemail.com>wrote:

[#393220] Re: Using _ like in Scala? — Robert Klemme <shortcutter@...> 2012/02/07

On Tue, Feb 7, 2012 at 1:00 PM, Josh Cheek <josh.cheek@gmail.com> wrote:

[#393240] Re: Using _ like in Scala? — Josh Cheek <josh.cheek@...> 2012/02/08

On Tue, Feb 7, 2012 at 9:15 AM, Robert Klemme <shortcutter@googlemail.com>wrote:

[#393254] Re: Using _ like in Scala? — Robert Klemme <shortcutter@...> 2012/02/08

On Wed, Feb 8, 2012 at 3:43 AM, Josh Cheek <josh.cheek@gmail.com> wrote:

[#393259] Re: Using _ like in Scala? — Josh Cheek <josh.cheek@...> 2012/02/08

On Wed, Feb 8, 2012 at 5:58 AM, Robert Klemme <shortcutter@googlemail.com>wrote:

[#393181] Tork 18.0.0 — "Suraj N. Kurapati" <sunaku@...>

Tork - Test with fork - https://github.com/sunaku/tork#readme

16 messages 2012/02/06
[#393183] Re: [ANN] Tork 18.0.0 — Bartosz Dziewoński <matma.rex@...> 2012/02/06

You have faster major version release cycle than Chrome...

[#393189] Re: [ANN] Tork 18.0.0 — Quintus <sutniuq@...> 2012/02/06

Am 06.02.2012 22:07, schrieb Bartosz Dziewoナгki:

[#393203] Re: Tork 18.0.0 — Suraj Kurapati <sunaku@...> 2012/02/07

Marvin Gテシlker wrote in post #1044440:

[#393347] Symbol garbage collection — Dido Sevilla <dido.sevilla@...>

I've always wondered why Ruby didn't do garbage collection of symbols,

13 messages 2012/02/10

[#393402] Who Administrates this list and how can the community help save this list from the noise. — andrew mcelroy <sophrinix@...>

It is very clear that this list has been under a incredibly heavy

21 messages 2012/02/11
[#393403] Re: Who Administrates this list and how can the community help save this list from the noise. — serialhex <serialhex@...> 2012/02/11

+1

[#393407] Re: Who Administrates this list and how can the community help save this list from the noise. — Cathy Alomari <cathy1428@...> 2012/02/11

Good luck, I doubt anyone is paying attention. I have seen numerous

[#393410] Re: Who Administrates this list and how can the community help save this list from the noise. — "Darryl L. Pierce" <mcpierce@...> 2012/02/11

On Sat, Feb 11, 2012 at 1:12 PM, Cathy Alomari <cathy1428@gmail.com> wrote:

[#393430] Re: Who Administrates this list and how can the community help save this list from the noise. — Cathy Alomari <cathy1428@...> 2012/02/13

On Sat, Feb 11, 2012 at 10:48 AM, Darryl L. Pierce <mcpierce@gmail.com>wrote:

[#393432] Re: Who Administrates this list and how can the community help save this list from the noise. — Bartosz Dziewoński <matma.rex@...> 2012/02/13

2012/2/13 Cathy Alomari <cathy1428@gmail.com>:

[#393434] Re: Who Administrates this list and how can the community help save this list from the noise. — Rimantas Liubertas <rimantas@...> 2012/02/13

> Have you tried mailing ruby-talk-ctl@ruby-lang.org (mailto:ruby-talk-ctl@ruby-lang.org) with "unsubscribe"

[#393412] the ruby syntax — maven apache <apachemaven0@...>

Hi:

19 messages 2012/02/12
[#393413] Re: the ruby syntax — Bartosz Dziewoński <matma.rex@...> 2012/02/12

When a hash is the last argument to a method, you can skip its open-

[#393416] Re: the ruby syntax — maven apache <apachemaven0@...> 2012/02/12

2012/2/12 Bartosz Dziewoナгki <matma.rex@gmail.com>

[#393435] Re: the ruby syntax — Saji Hameed <saji@...> 2012/02/13

On Sun, Feb 12, 2012 at 10:49 PM, maven apache <apachemaven0@gmail.com> wrote:

[#393546] Difference between 1.9.2 and 1.9.3 — James French <James.French@...>

module A <- line 1

12 messages 2012/02/20

[#393548] Accessing a local variable through a symbol — Ralph Shnelvar <ralphs@...32.com>

Let's say I have

11 messages 2012/02/20

[#393671] Rubymoticons — Dave Aronson <rubytalk2dave@...>

I was demonstrating injection of a symbol, and noticed a familiar

12 messages 2012/02/28

Re: Multiple assignment in conditional

From: Josh Cheek <josh.cheek@...>
Date: 2012-02-01 21:03:28 UTC
List: ruby-talk #392968
On Wed, Feb 1, 2012 at 5:49 AM, Gavin Sinclair <gsinclair@gmail.com> wrote:

> On Tue, Jan 31, 2012 at 6:22 PM, Josh Cheek <josh.cheek@gmail.com> wrote:
>
> >> # The following causes a SyntaxError: multiple assignment in
> conditional.
> >> if (a, b = foo)
> >>  puts a
> >> end
>
> > What did you expect your real code to do? It seems to me that it should
> > raise an error unless it's an array of size 2
>
> Nope.  It can return anything at all and Ruby will deal with it.
> Parallel assignment is (thankfully) flexible.
>
> def foo; 1; end
> a, b = foo            # returns 1; a == 1, b == nil
>
> def bar; [1,2,3,4,5]; end
> a, b = bar            # returns [1,2,3,4,5]; a == 1, b == 2
>
> > and if it is, then it should
> > return an array of size two, making the conditional necessarily true.
>
> Nope.  The conditional can be false.
>
> def foo; nil; end
> a, b = foo            # returns nil; a == nil, b == nil
>
> > So I don't know what you were expecting to happen.
>
> def foo; nil; end
>
> if (a, b = foo)
>   puts "outcome 1"
> else
>  puts "outcome 2"   # I was expecting this.
> end
>
> Of course I don't have a function that returns nil unconditionally!
> Just showing the structure.
>
>
Sorry, but I find this incredibly opaque.

Could you just write what you expect the evaluation to be in each of these
cases?

a, b = 1, 1
a, b = 1, nil
a, b = nil, 1
a, b = nil, nil

I'd expect return values of [1, 1], [1, nil], [nil, 1], [nil, nil] which
are all true.

Now does this change when the RHS is an array instead of two values?
For example, would `a, b = [1, 1]` return a different value than `a, b =
[1, 1]`?


Your example seems particularly devious in that it only has one value on
the RHS of the assignment. This means that the second argument will be
assigned nil (because there is no value for it), and because assignment
operators always return the RHS, it will then return whatever single value
was over there. This causes it to look like you are assigning multiple
values to the variables and having it return nil, when in fact you are only
assigning one value (the second variable is along for the ride and will
always be nil).

There are so many nuanced ruby edge cases one must know (and then must also
know the implementation of how it is being returned) to understand that
example that I think it has more overhead than it is worth.

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