From: Matthew Smillie <M.B.Smillie@...>
Date: 2006-08-10T01:50:33+09:00
Subject: Re: how to see if a variable matches an array element?

On Aug 9, 2006, at 17:35, John Fink wrote:

> Hey folks,
>
> I'm knocking together a Rock, Paper, Scissors Ruby script to teach  
> myself
> more Ruby deliciousness, and I've got it working, except I want to  
> compare a
> variable to an array element (one of ["R", "P", "S"]) and have the  
> program
> die if it doesn't match up.
>
> Here's the relevant part of my script (note the rochambo function  
> is defined
> earlier in the script, and is really verbose, so I clipped it out):
>
> choices = %w{R P S}
> puts "Your choice? R,P,S"
> userchoice = gets.chomp.upcase
> computerchoice = choices[rand(choices.length)]
> puts "You picked " + userchoice + "!"
> puts "Computer picked " + computerchoice + "!"
> puts "FIGHT!"
> rochambo(userchoice, computerchoice)
>
>
> Basically I want to have the program die if the userchoice variable  
> doesn't
> equal one of the elements in the choices array, and it should be  
> easy, but I
> am hitting my head against a wall.

Check the documentation for the Array class at http://ruby-doc.org/core

exit unless choices.include? userchoice

will accomplish what you're looking for, though there are quite a few  
other ways to do it.

matthew smillie.