From: Gabriele Marrone <gabriele.marrone@...>
Date: 2006-11-12T05:35:12+09:00
Subject: Re: print message if user does nothing for x seconds?


On 11/nov/06, at 21:07, ara.t.howard@noaa.gov wrote:

> if you're on windows give up now.  otherwise try this:
>
>     harp:~ > cat a.rb
>     require 'timeout'
>
>     def prompt question, opts = {}
>       timeout = Integer(opts['timeout'] || opts[:timeout] || 42)
>       max = Integer(opts['max'] || opts[:max] || 42)
>       default = opts['default'] || opts[:default]
>       prod = (opts['prod'] || opts[:prod] || 'hey! wake up!').to_s
>
>       answer = default
>       prompt = "\r#{ question }: "
>       prod = "\r#{ prod }"
>
>       if prompt.size > prod.size
>         prod += (' ' * (prompt.size - prod.size))
>       end
>       if prod.size > prompt.size
>         prompt += (' ' * (prod.size - prompt.size))
>       end
>
>       max.times{
>         begin
>           print prompt
>           STDOUT.flush
>           Timeout::timeout(timeout){ answer = gets }
>           break
>         rescue Timeout::Error
>           print prod
>           STDOUT.flush
>           sleep 2
>         end
>       }
>
>       answer
>     end
>
>     answer = prompt 'the question', 'timeout' => 5, 'max' => 2
>
>     p 'answer' => answer

Nice! May I suggest adding an optional validation block?
I hope you don't mind if I slightly modify your code:


def prompt question, opts = {}, &validation
   timeout = Integer(opts['timeout'] || opts[:timeout] || 42)
   max = Integer(opts['max'] || opts[:max] || 42)
   default = opts['default'] || opts[:default]
   prod = (opts['prod'] || opts[:prod] || 'hey! wake up!').to_s
   invalid = (opts['invalid'] || opts[:invalid] || 'try again').to_s

   answer = default
   prompt = "\r#{ question }: "
   prod = "\r#{ prod }"

   if prompt.size > prod.size
     prod += (' ' * (prompt.size - prod.size))
   end
   if prod.size > prompt.size
     prompt += (' ' * (prod.size - prompt.size))
   end

   max.times{
     begin
       print prompt
       STDOUT.flush
       Timeout::timeout(timeout){ answer = gets }
       if validation && !validation.call(answer)
         answer = default
         puts invalid
       else
         break
       end
     rescue Timeout::Error
       print prod
       STDOUT.flush
       sleep 2
     end
   }

   answer
end


answer = prompt('the question', 'timeout' => 5, 'max' => 2) { |s| s  
== "valid input\n" }

--
Gabriele Marrone