From: Robert Klemme <shortcutter@...>
Date: 2007-03-11T07:45:07+09:00
Subject: Re: OpenStruct,, know what keys are set

On 10.03.2007 17:54, Aaron Smith wrote:
>> Um, for what implementation of "keys_added"?  The comment points out
>> that it always returns nil - I suspect you just measured performance of
>> an OpenStruct ad hoc getter:
>>
>> irb(main):005:0> OpenStruct.new.keys_added
>> => nil
>> irb(main):006:0> OpenStruct.new.foo_bar
>> => nil
>>
>> Kind regards
>>
>>   robert
> 
> Ah yes, you caught me. I completely overlooked this code in the above 
> exmaple:
> class OpenStruct
>   def keys_added
>     @table.keys.map{|k| k.to_s}
>   end
> end
> 
> 
> --
> New Tests:
> 
> require 'ostruct'
> require 'benchmark'
> 
> class OpenStruct
>   def keys_added
>     @table.keys.map{|k| k.to_s}
>   end
> end
> 
> lady = OpenStruct.new
> 0.upto(10) do |i|
>   eval("lady.cat#{i} = i")
>   #puts eval("lady.cat#{i}")
> end
> 
> Benchmark.bm do |x|
>   x.report("Find all keys 1"){lady.methods(false).grep(/[^=]$/)}
>   x.report("Find all keys 2"){lady.instance_variable_get("@table").keys}
>   x.report("Find all keys 3"){lady.keys_added}
>   x.report("Find all keys 
> 4"){lady.instance_variable_get("@table").keys.map{|k| k.to_s }}
> end
> 
> 
> #puts "\n" + lady.methods(false).grep(/[^=]$/).to_s
> #puts "\n" + lady.instance_variable_get("@table").keys.to_s
> #puts "\n" + lady.keys_added.to_s
> #puts "\n" + lady.instance_variable_get("@table").keys.map{|k| k.to_s 
> }.to_s
> 
> 
> OUTPUT:
>                  user     system      total        real
> Find all keys 1  0.000000   0.000000   0.000000 (  0.000077)
> Find all keys 2  0.000000   0.000000   0.000000 (  0.000014)
> Find all keys 3  0.000000   0.000000   0.000000 (  0.000017)
> Find all keys 4  0.000000   0.000000   0.000000 (  0.000016)
> 

You should add iterations to the blocks - otherwise the figures are 
pretty uninformative. :-)  Using bmbm (with rehearsal) might also be a 
good idea.

Kind regards

	robert