[#377882] remove array bracket — Kamarulnizam Rahim <niezam54@...>

Hi when i run my script, the output is as followed:

18 messages 2011/02/02

[#378046] Setter method for Hash value — Rolf Pedersen <rolfhsp@...>

Hi

20 messages 2011/02/03
[#378052] Re: Setter method for Hash value — Brian Candler <b.candler@...> 2011/02/03

Rolf Pedersen wrote in post #979431:

[#378056] Re: Setter method for Hash value — Rolf Pedersen <rolfhsp@...> 2011/02/03

Hi Brian (and others who have contributed with suggestions along the same

[#378144] C extension: How to check if a VALUE is still alive (not being GC'ed)? — Iñaki Baz Castillo <ibc@...>

Hi, I'm coding an async DNS resolver for EventMachine based on udns (a

13 messages 2011/02/05
[#378171] Re: C extension: How to check if a VALUE is still alive (not being GC'ed)? — Tony Arcieri <tony.arcieri@...> 2011/02/06

On Sat, Feb 5, 2011 at 4:02 PM, Iki Baz Castillo <ibc@aliax.net> wrote:

[#378179] Re: C extension: How to check if a VALUE is still alive (not being GC'ed)? — Iñaki Baz Castillo <ibc@...> 2011/02/06

2011/2/6 Tony Arcieri <tony.arcieri@medioh.com>:

[#378199] Choosing an office suite — Hilary Bailey <my77elephants@...>

I am trying to decide which office suite to choose from. The only

30 messages 2011/02/07
[#378229] Re: Choosing an office suite — Phillip Gawlowski <cmdjackryan@...> 2011/02/07

On Mon, Feb 7, 2011 at 11:15 AM, Hilary Bailey <my77elephants@gmail.com> wrote:

[#378202] making hash key from arrays — Arihan Sinha <arihan_sinha@...>

Hi All,

11 messages 2011/02/07

[#378254] "permission denied" happening too often — Peter Bailey <pbailey@...>

Hello,

15 messages 2011/02/08
[#378256] Re: "permission denied" happening too often — Anurag Priyam <anurag08priyam@...> 2011/02/08

> I've got Ruby scripts that have been working fine for years now. But,

[#378257] Re: "permission denied" happening too often — Markus Schirp <mbj@...> 2011/02/08

You can also try to strace your script. In the logs you'll find the system

[#378259] Re: "permission denied" happening too often — Peter Bailey <pbailey@...> 2011/02/08

Markus Schirp wrote in post #980289:

[#378307] undefined class/module YAML::PrivateType - Error — "Priya D." <dharsininitt@...>

Hi,

11 messages 2011/02/09

[#378341] System calls with ` in parameters — "Gerad S." <geradstemke@...>

Hi All,

12 messages 2011/02/09

[#378618] Defining class methods — Tony Arcieri <tony.arcieri@...>

It seems there are 3 ways of defining class methods (at least in common

12 messages 2011/02/16

[#378685] LiveAST: a pure Ruby 1.9.2 library obtaining live abstract syntax trees — "James M. Lawrence" <quixoticsycophant@...>

= LiveAST

13 messages 2011/02/18

[#378753] posix_mq : Problem installing on HPUX — Tadeusz Bochan <tad.bochan@...>

Hello,

13 messages 2011/02/20

[#378890] a, b = Array.new(2).map!{|x| data.dup} — Stefan Salewski <mail@...>

I think I can replace this code

19 messages 2011/02/23
[#378892] Re: a, b = Array.new(2).map!{|x| data.dup} — niklas | brueckenschlaeger <niklas@...> 2011/02/23

Are you sure you can't rework your code to *not* copy data 5x? I assume

[#378899] Re: a, b = Array.new(2).map!{|x| data.dup} — Stefan Salewski <mail@...> 2011/02/23

On Thu, 2011-02-24 at 07:00 +0900, niklas | brueckenschlaeger wrote:

[#378941] Automatic question generator libs in Ruby Language — Sniper Abandon <sathish.salem.1984@...>

is there any Automatic question generator libraries in Ruby Language ?

20 messages 2011/02/24
[#379058] Re: Automatic question generator libs in Ruby Language — Sniper Abandon <sathish.salem.1984@...> 2011/02/27

suppose if i have a paragraph (arround 250 words)

[#379172] Re: Automatic question generator libs in Ruby Language — Shadowfirebird <shadowfirebird@...> 2011/03/01

> i want to get all the possible question from that paragraph

[#379174] Re: Automatic question generator libs in Ruby Language — Peter Zotov <whitequark@...> 2011/03/01

On Tue, 1 Mar 2011 19:31:36 +0900, Shadowfirebird wrote:

[#379175] Re: Automatic question generator libs in Ruby Language — Adam Prescott <mentionuse@...> 2011/03/01

On Tue, Mar 1, 2011 at 10:55 AM, Peter Zotov <whitequark@whitequark.org>wrote:

[#379177] Re: Automatic question generator libs in Ruby Language — Peter Zotov <whitequark@...> 2011/03/01

On Tue, 1 Mar 2011 20:02:13 +0900, Adam Prescott wrote:

[#379179] Re: Automatic question generator libs in Ruby Language — Adam Prescott <mentionuse@...> 2011/03/01

On Tue, Mar 1, 2011 at 12:28 PM, Peter Zotov <whitequark@whitequark.org>wrote:

[#378949] why is $1 in a grep() equal to nil? — 7stud -- <bbxx789_05ss@...>

class DataSource

16 messages 2011/02/24
[#378953] Re: why is $1 in a grep() equal to nil? — Eric Christopherson <echristopherson@...> 2011/02/25

On Thu, Feb 24, 2011 at 2:59 PM, 7stud -- <bbxx789_05ss@yahoo.com> wrote:

[#378958] parsing rule for this code? — 7stud -- <bbxx789_05ss@...>

1)

11 messages 2011/02/25

[#379000] Symbol#to_proc helping out with #select to beat Scala-s solution — Jarmo Pertman <jarmo.p@...>

Hey!

9 messages 2011/02/25

[#379074] finding a tag in a binary file — rob stanton <tnotnats@...>

I have a binary file in which I'd like to find multiple strings of 10

12 messages 2011/02/27

Re: Setter method for Hash value

From: Jes俍 Gabriel y Gal疣 <jgabrielygalan@...>
Date: 2011-02-07 08:57:09 UTC
List: ruby-talk #378196
On Sun, Feb 6, 2011 at 10:23 PM, Rolf Pedersen <rolfhsp@gmail.com> wrote:
> 2011/2/4 Jes俍 Gabriel y Gal疣 <jgabrielygalan@gmail.com>
>
>> For the other two, you need a proxy object that can delegate [] and
>> []= to DataClass too. For this to work, MyClass#props needs to wrap
>> the actual hash returned by DataClass with a wrapper object (Props).
>> As you need this proxy object to have some hash like behaviour, you
>> can implement whatever methods you need to behave like a hash. As an
>> example, apart from [] and []= I have implemented inspect and to_s.
>>
>>
> Instead of implementing other methods to make the wrapper object behave more
> like a Hash object, why not let Props inherit Hash, and just redefine those
> methods that I need to behave differently? Perhaps like this:
>
> class Props < Hash
> ef initialize h
> eplace h
> nd
> ef [](key)
> ..
> nd
> ef []=(key, value)
> ..
> nd
> end

Hi,

In fact I was going to follow up the discussion with a further idea.
What I sent has a flaw, and it's the fact that the Props object gets
initialized with the hash, while ideally it should delegate also all
reads to the DataClass. It doesn't make sense to have a reference to
the resulting hash. This way, if the hash in DataClass is modified by
other means, the new values will be available to all instances of
Props (in the current implementation this might be true, because we
are returning references to the same hash, but this can be a weak
point). It's cleaner this way, in my opinion:

class MyClass
 def props
   Props.new
 end

 def props=(h)
   DataClass::set_props h
 end
end

class Props
 def [](key)
   DataClass::get_prop key
 end

 def []=(key,value)
   DataClass::set_prop key,value
 end

 def inspect; DataClass::get_props.inspect; end
 def to_s; DataClass::get_props.to_s; end
end


class DataClass
 @data = {:a=>1, :b=>2, :c=>3}
 def self.get_props()
   @data
 end
 def self.get_prop(key)
   @data[key]
 end
 def self.set_props(data)
   @data = data
 end
 def self.set_prop(key, value)
   @data[key] = value
 end
end

As for your question about inheriting from Hash: read a bit about
Inheritance vs Composition. It's generally considered that Composition
is more flexible.

Jesus.

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