From: Gavin Kistner <gavin@...>
Date: 2004-02-15T03:29:59+09:00
Subject: Re: noobie question - module/class vs obj

Paul Vudmaska wrote:
>In simular situations w/javscript i do this:
>    instead of:
>    function class(){
>       this.prop = 0
> 
>    }
>    obj = new class
 >
>   ... I use
 >
>    obj = {
>       prop : 0
>    }
 >
> Which is kinda what i'm shooting for in Ruby.

Well, in JS that's creating an Object literal, rather than creating a 
class. The equivalents in ruby would be either a Hash literal:

obj = { 'prop' => 0 }

or a Singleton design.

See:

http://phrogz.net/ProgrammingRuby/frameset.asp?content=intro.asp%23arraysandhashes
and
http://phrogz.net/ProgrammingRuby/frameset.asp?content=language.asp%23hashes

for information on Hashes, and

http://phrogz.net/ProgrammingRuby/frameset.asp?contenttut_classes.asp%23singletonsandotherconstructors
and
http://phrogz.net/ProgrammingRuby/frameset.asp?content=lib_patterns.asp%23singleton

for information on Singletons.


> 2) I thot i would include a module with some generic class methods 
> into a class ie:
>    module Somemodule
>          self.boo
>                puts 'boo'
>          end
>    end
>    class SomeClass
>       include Somemodule
> 
>        self.boohoo
>                       # puts boo #dies cant find SomeClass method boo
>             puts Somemodule.boo #works ok
>                  end
>    end

If you're talking about instance methods, you want:

module Somemodule
	def boo
		puts 'boo'
	end
end
class SomeClass
	include Somemodule
	def boohoo
		boo
	end
end


If you're talking about class methods, then you want:

module Somemodule
	def self.boo
		puts 'boo'
	end
end
class SomeClass
	include Somemodule
	def self.boohoo
		self.class.boo
	end
end