Delegating class methods

ruby-talk
1

class Klass

   extend Forwardable

   def_delegators :@object :method1, :method2, :method3

    def initialize
       @object = SomeKlass.new
    end

end

···

Hi all,

how would you forward calls from class methods to a class atribute?
Like in:

class Foo
  @@hash = {}

  def self.size
    @@hash.size
  end
end

I have to delegate a fairly large number of calls to an attribute. I'm
currently using method_missing, but I was wondering if there was a
cleaner way to do that as the method names are known at load time. I
didn't find any using the standard library. Perhaps using some
metaprogramming.

Thanks!

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2

No, that would forward to an instance variable and only work with
Klass instances.

If the OP doesn't mind using a singleton class variable instead of a
class variable [1], then we can still use forwardable:

class Foo
  @hash = {}
  class << self
    extend Forwardable
    def_delegators :@hash, :, :=, :size
  end
end

Foo[:bar] = 'baz'
Foo.size #=> 1

Solidarity,
lasitha

[1] Generally a good idea anyway, right?

···

On Mon, Mar 2, 2009 at 2:27 AM, Michael Malone <michael.malone@tait.co.nz> wrote:

On Mon, Mar 2, 2009 at 2:03 AM, abc <arcadiorubiogarcia@gmail.com> wrote:

how would you forward calls from class methods to a class atribute?
[...]

I have to delegate a fairly large number of calls to an attribute. [...]

class Klass
extend Forwardable
def_delegators :@object :method1, :method2, :method3

  def initialize
     @object = SomeKlass.new
  end
end