Re: Initialize Struct from Hash

Path	csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!news.dougwise.org!nntpfeed.proxad.net!proxad.net!feeder1-2.proxad.net!usenet-fr.net!de-l.enfer-du-nord.net!feeder2.enfer-du-nord.net!talisker.lacave.net!lacave.net!not-for-mail
From	Joel VanderWerf <joelvanderwerf@gmail.com>
Newsgroups	comp.lang.ruby
Subject	Re: Initialize Struct from Hash
Date	Fri, 29 Apr 2011 10:27:49 -0500
Organization	Service de news de lacave.net
Lines	51
Message-ID	<4DBAD8F0.8000202@gmail.com> (permalink)
References	<919600ef40c16b10cb0f01a757234376@ruby-forum.com> <69c1ac462d5ff72621121fcf6c8135ec@ruby-forum.com> <4DB9D327.9000905@gmail.com> <BANLkTikR=wRKtkfe46=j+apo9bLRR-CHgQ@mail.gmail.com>
NNTP-Posting-Host	bristol.highgroove.com
Content-Type	text/plain; charset=ISO-8859-1
Content-Transfer-Encoding	7bit
X-Trace	talisker.lacave.net 1304090895 96998 65.111.164.187 (29 Apr 2011 15:28:15 GMT)
X-Complaints-To	abuse@lacave.net
NNTP-Posting-Date	Fri, 29 Apr 2011 15:28:15 +0000 (UTC)
In-Reply-To	<BANLkTikR=wRKtkfe46=j+apo9bLRR-CHgQ@mail.gmail.com>
X-Received-From	This message has been automatically forwarded from the ruby-talk mailing list by a gateway at comp.lang.ruby. If it is SPAM, it did not originate at comp.lang.ruby. Please report the original sender, and not us. Thanks! For more details about this gateway, please visit: http://blog.grayproductions.net/categories/the_gateway
X-Mail-Count	382387
X-Ml-Name	ruby-talk
X-Rubymirror	Yes
X-Ruby-Talk	<4DBAD8F0.8000202@gmail.com>
Xref	x330-a1.tempe.blueboxinc.net comp.lang.ruby:3702

Show key headers only | View raw

On 04/29/2011 01:06 AM, Robert Klemme wrote:
> On Thu, Apr 28, 2011 at 10:50 PM, Joel VanderWerf
> <joelvanderwerf@gmail.com>  wrote:
>
>> Tangentially, I wonder if anything like the following (very rough proof of
>> concept) has been used instead of Struct.
>>
>> class Hash
>>   def structify!
>>     keys.each do |key|
>>       class<<  self; self; end.class_eval do
>>         define_method key do
>>           fetch key
>>         end
>>         define_method "#{key}=" do |val|
>>           store key, val
>>         end
>>       end
>>     end
>>   end
>> end
>>
>> h = {:foo =>  1, :bar =>  2}
>> h.structify!
>> p h.foo # 1
>> h.foo = 3
>> p h.foo # 3
>> p h     # {:foo=>3, :bar=>2}
>> p h.oof # undefined
>
> irb(main):004:0>  h = {:foo =>  1, :bar =>  2}
> =>  {:foo=>1, :bar=>2}
> irb(main):005:0>  o = OpenStruct.new(h)
> =>  #<OpenStruct foo=1, bar=2>
> irb(main):006:0>  o.foo
> =>  1
> irb(main):007:0>  o.bar
> =>  2
>
> Well, here we differ
>
> irb(main):008:0>  o.oof
> =>  nil
>
> But the issue with your approach is that it is not dynamic.  Keys
> added or removed after call to #structify! will not be taken care of.
> A more dynamic approach would be

That's intended: #structify is supposed to turn a hash into something 
that looks like a Struct, not an OpenStruct.

Thread

Initialize Struct from Hash Brian Candler <b.candler@pobox.com> - 2011-04-28 12:00 -0500
  Re: Initialize Struct from Hash Jesús Gabriel y Galán <jgabrielygalan@gmail.com> - 2011-04-28 12:05 -0500
    Re: Initialize Struct from Hash Jesús Gabriel y Galán <jgabrielygalan@gmail.com> - 2011-04-28 12:10 -0500
    Re: Initialize Struct from Hash 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-28 12:16 -0500
      Re: Initialize Struct from Hash Jesús Gabriel y Galán <jgabrielygalan@gmail.com> - 2011-04-28 12:19 -0500
  Re: Initialize Struct from Hash Brian Candler <b.candler@pobox.com> - 2011-04-28 15:24 -0500
    Re: Initialize Struct from Hash Joel VanderWerf <joelvanderwerf@gmail.com> - 2011-04-28 15:50 -0500
      Re: Initialize Struct from Hash Robert Klemme <shortcutter@googlemail.com> - 2011-04-29 03:06 -0500
        Re: Initialize Struct from Hash Joel VanderWerf <joelvanderwerf@gmail.com> - 2011-04-29 10:27 -0500
      Re: Initialize Struct from Hash Brian Candler <b.candler@pobox.com> - 2011-04-29 03:22 -0500

csiph-web