From: Erik Veenstra <erikveen@...>
Date: 2006-07-13T22:18:39+09:00
Subject: Re: Recursion and Ruby

> Try CachedProc

I could easily implement a cache myself, even a cleaner one
(see below), but that's not my point. My point is: Why is a
lambda call much slower then a method call?

gegroet,
Erik V. - http://www.erikveen.dds.nl/

----------------------------------------------------------------

 # Without cache.

 fib     = lambda{|n| n<=1 ? 1 : fib[n-1] + fib[n-2]}

 0.upto(30){|i| puts "The  #{i} Fibonacci number is #{fib[i]}"}

----------------------------------------------------------------

 # With cache.

 fib     = lambda{|n| n<=1 ? 1 : fib[n-1] + fib[n-2]}

 cache   = lambda{|f| h={} ; lambda{|*args| h[*args] ||= f[*args]}}
 fib     = cache[fib]

 0.upto(30){|i| puts "The  #{i} Fibonacci number is #{fib[i]}"}

----------------------------------------------------------------