[ruby-core:28767] Re: [Feature #2065] An ancestors iterator

Hi Simon,

2010/3/19 Simon Chiang <[e-mail]>:
> This is for 100k iterations, so no it's not a bottleneck but likewise that's not why I make this request. I make the request because it would be significantly faster to not generate the ancestors array each time (~20% in this case, which illustrates what is probably the maximum increase for getting an each_ancestor iterator).

I cannot get your point.  If you admit it is not bottleneck, I wonder
why you hope it faster.
You should know adding a method is not free in terms of maintenance.


> Ok, I attached a benchmark that is designed to measure the time required for generating the ancestors array.

Thanks, I could understand what you want to do.

If you want speed at any rate, how about manual search by using
Class#superclass?
It is probably faster than each_ancestor because it does not
yield a block.


  module Dsl2
    def self.extended(base)
      base.registry ||= {}
    end

    def inherited(base)
      base.registry ||= {}
    end

    attr_accessor :registry

    def set(key, value)
      registry[key] = value
    end

    def value(key)
      klass = self
      while klass
        if klass.registry.has_key?(key)
          return klass.registry[key]
        end
        klass = klass.superclass
      end
    end
  end


Benchmark without cache
                          user     system      total        real
A.value(:one)         0.340000   0.000000   0.340000 (  0.340906)
B.value(:two)         0.340000   0.000000   0.340000 (  0.349000)
C.value(:three)       0.360000   0.000000   0.360000 (  0.357215)

Benchmark with cache
                          user     system      total        real
A.value(:one)         0.240000   0.000000   0.240000 (  0.235161)
B.value(:two)         0.230000   0.000000   0.230000 (  0.236722)
C.value(:three)       0.240000   0.000000   0.240000 (  0.233931)
Array.new             0.080000   0.000000   0.080000 (  0.084003)

Benchmark with manual search
                          user     system      total        real
A2.value(:one)        0.130000   0.000000   0.130000 (  0.122530)
B2.value(:two)        0.120000   0.000000   0.120000 (  0.120361)
C2.value(:three)      0.110000   0.000000   0.110000 (  0.119009)

-- 
Yusuke ENDOH <[e-mail]>