From: Robert Klemme <shortcutter@...>
Date: 2011-03-23T18:26:06+09:00
Subject: Re: Dynamically calling a certain set of methods

On Wed, Mar 23, 2011 at 9:32 AM, Vicente Bosch Campos <vbosch@gmail.com> wrote:
> Hi,
>
> I am doing an implementation of a genetic algorithm to resolve a certain type of equations. I need to randomly call a certain method from a set:
>
>    def mutation
>
>      self.send(self.methods.select!{|element| element.to_s.end_with?("Mutation")}.shuffle![0])     #I'm using to_s as the symbol object do not allow end_with?
>
>    end
>
>    def operatorSwitchMutation
>    end
>
>    def numberSwitchMutation
>    end
>
>    def unusedNumberMutation
>    end
>
>
> Is self.send(self.methods.select!{|element| element.to_s.end_with?("Mutation")}.shuffle![0]) the best way to do it ? Is there a more ruby idiom to perform the safe thing ?

First of all you can save typing by removing "self.".  Then you should
replace #shuffle![0] with #sample:

send(methods.select!{|element| element.to_s.end_with?("Mutation")}.sample)

If you like you can strip this down even further by using regular
expressions because those happen to work with Symbols as well:

send(methods.grep(/Mutation\z/).sample)

:-)

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/