ahoward / wrap Goto Github PK

NAME
  wrap

SYNOPSIS
  non-sucking :before and :after filters for any ruby class

DESCRIPTION
  yes yes, active_support does this.  but crapily.  with active_support you'll
  need to do this


    class Record
      include ActiveSupport::Callbacks
      define_callbacks :save

      def save
        run_callbacks :save do
          puts "- save"
        end
      end
    end

  but hey, if a subclass forgets to call 'super' or doesn't manually run
  'run_callbacks' the codez are *screwed*.  that sux.  why not this?


    class Record
      include Wrap

      wrap :save
    end


  yes, it's that simple.  you can now do

    class SubRecord < Record
      before :save do
        special_sauce
      end
      
      def save
        no_special_sauce
      end
    end

  did you get that?  the :before and :after hooks will be called no matter
  what the subclass does.  the method will be wrapped, period.  no special
  work required.  of course, if the sublcass messes with 'method_added' their
  will be hell to pay.  that's the price for simplicity.

  the callbacks are very close, but not identical to active_supports.  you can
  return 'false' to halt the chain, but you can also simply call 'halt!'.
  another neat trick is that :before callbacks will be called with the
  arguments to the wrapped method itself iff possible and :after callbacks
  will be called with the result of the wrapped method, iff possible.

  the test suite reads pretty damn clean.  have a go.