Comments on: One line Ruby memoization http://unintelligible.org/blog/2007/08/16/one-line-ruby-memoization/ Fri, 05 Sep 2008 19:30:27 +0000 http://wordpress.org/?v=2.6 By: Nick http://unintelligible.org/blog/2007/08/16/one-line-ruby-memoization/#comment-39 Nick Fri, 17 Aug 2007 19:27:13 +0000 http://unintelligible.org/blog/2007/08/16/one-line-ruby-memoization/#comment-39 Much cleaner indeed. I think what I best liked about that technique was the idea of the method redefining itself, although it's obviously in need of a better application... Much cleaner indeed. I think what I best liked about that technique was the idea of the method redefining itself, although it’s obviously in need of a better application…

]]> By: Shadowfiend http://unintelligible.org/blog/2007/08/16/one-line-ruby-memoization/#comment-38 Shadowfiend Fri, 17 Aug 2007 17:27:35 +0000 http://unintelligible.org/blog/2007/08/16/one-line-ruby-memoization/#comment-38 It bears mentioning that the standard way of doing memoization in Ruby is using the ||= operator, and that seems to run much faster. The code: <code>class Memoized def memoized_method @result ||= lambda { puts 'computing expensive value'; sleep 2; 'hello world' }.call end end</code> The timing: <code>Rehearsal ------------------------------------ 0.040000 0.010000 0.050000 ( 2.055683) --------------------------- total: 0.050000sec user system total real 0.050000 0.010000 0.060000 ( 0.055465)</code> It bears mentioning that the standard way of doing memoization in Ruby is using the ||= operator, and that seems to run much faster.

The code:

class Memoized
def memoized_method
@result ||= lambda { puts 'computing expensive value'; sleep 2; 'hello world' }.call
end
end

The timing:

Rehearsal ------------------------------------
0.040000 0.010000 0.050000 ( 2.055683)
--------------------------- total: 0.050000sec

user system total real
0.050000 0.010000 0.060000 ( 0.055465)

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