From: Joel VanderWerf <joelvanderwerf@...>
Date: 2011-05-08T07:56:47+09:00
Subject: Re: Help with while condition OR condition

On 05/07/2011 03:37 PM, Bill W. wrote:
> Hi everyone,
>
> This is my first post, so I hope I don't sound too inexperienced..
>
> I'm trying to teach myself Ruby, and have run into an issue with a while
> statement that will break if an input is "exit" or "quit".
> As of right now, it works if exit is input, but not quit
>
> I know I am completely misusing the entire thing, but here is what I
> came up with:
>
> EXIT = "exit"  #need constants since Ruby gets pissed at string literals
> QUIT = "quit"  #in a comparison
>
> print "Input: "
> input = gets
> while input.chomp.downcase != (EXIT || QUIT) #only works for exit

It can help to take apart expressions in irb (interactive ruby):

$ irb
 >> EXIT = "exit"
=> "exit"
 >> QUIT = "quit"
=> "quit"
 >> EXIT || QUIT
=> "exit"
 >> "quit" == (EXIT || QUIT)
=> false

>    #Do something
>
> print "Input: "  #pick up the next input and check it
> input = gets
> end
>
> I know that Ruby has a lot of shortcuts, but if you post any please
> explain how they work (or provide a link to a good explanation.

Something to tinker with:

print "Input: "
while input = gets
   case s = input.chomp.downcase
   when "exit", "quit"
     puts "You wanted to #{s} this mighty fine program?"
     break
   else
     puts "Why do you say '#{s}'?"
     print "Input: "
   end
end
puts "Done."