gistfile1.rb

#! /usr/bin/env ruby
# -*- coding: utf-8 -*-

# You need a jQuery library: ./public/javascripts/jquery.js
# Run: ruby app.rb -s mongrel

require 'rubygems'
require 'sinatra'
require 'haml'
require 'sass'

trap(:USR1) { ENV['typenow.go'] = 'true' }

get '/' do
  haml :index
end

post '/type' do
  ENV['typenow.val'] = params[:value]
  Process.kill :USR1, $$
end

get '/wait' do
  ENV['typenow.go'] = 'false'
  start = Time.now
  loop do
    break if ENV['typenow.go'] == 'true'
    break if (Time.now - start) > 30
    sleep 0.05
  end
  ENV['typenow.go'] == 'true' ?  ENV['typenow.val'] : halt(304)
end

__END__

@@ layout
!!! XML
!!! Strcit
%html{ :xmlns => 'httj://www.w3.org/1999/xhtml' }
  %head
    %meta{ :'http-equiv' => 'Content-Type', :content => 'text/html', :charset => 'utf-8' }
    %script{ :type => 'text/javascript', :src => 'javascripts/jquery.js' }
    :javascript
      (function() {
        var error_count = 0;
        var waiting = function() {
          $.ajax({
            url: '/wait',
            success: function(res) {
              if (res) {
                $('#result').text(res);
              }
              waiting();
            },
            error: function() {
              if (++error_count == 5) { return false; }
              waiting();
            }
          });
        }
        $(function () {
          waiting();
          var type = function() {
            var val = $('#type').val();
            $.post('/type', { value: val }, function() {});
          }
          $('input#type').keypress(type).keydown(type).keyup(type);
        });
      })();
  %body
    %h1 Typenow
    = yield

@@ index
#result{ :style => 'width: 500px; height: 30px; border: 1px solid #aaa' }
%input#type