From: Dominik Bathon <dbatml@...>
Date: 2006-07-13T19:12:22+09:00
Subject: Re: Recursion and Ruby

On Thu, 13 Jul 2006 10:57:29 +0200, Erik Veenstra <erikveen@gmail.com>  
wrote:

> You could use "case" as well (see version 2). It's faster.
> Using an ordinary if..else (without the elsif part) is faster
> (see version 3). And version 4 is once again faster.
>
> 4 is faster than 3 is faster than 2 is faster than 1...
>
> gegroet,
> Erik V. - http://www.erikveen.dds.nl/
>
> ----------------------------------------------------------------
>
>  Version 1   100,0%
>  Version 2   90,3%
>  Version 3   72,7%
>  Version 4   70,2%
>
> ----------------------------------------------------------------

Actually version 3 and version 4 are exactly equivalent for Ruby, it  
parses them both as NODE_IF:

>> pp "if a; b; else; c; end".parse_to_nodes.transform
[:if,
  {:body=>[:vcall, {:mid=>:b}],
   :else=>[:vcall, {:mid=>:c}],
   :cond=>[:vcall, {:mid=>:a}]}]
=> nil
>> pp "a ? b : c".parse_to_nodes.transform
[:if,
  {:body=>[:vcall, {:mid=>:b}],
   :else=>[:vcall, {:mid=>:c}],
   :cond=>[:vcall, {:mid=>:a}]}]
=> nil


Dominik