avalanche123 · March 9, 2012 05:34 · Mar 9, 2012
diff --git a/greenlet.rb b/greenlet.rb
@@ -0,0 +1,94 @@
+class String
+
+  def start_with?(little_string)
+    !self.match(/^#{Regexp.escape(little_string)}/).nil?
+  end
+
+  def end_with?(little_string)
+    !self.match(/#{Regexp.escape(little_string)}$/).nil?
+  end
+
+end
+
+class Greenlet
+  require 'fiber'
+
+  current = begin
+    instance = allocate
+    instance.instance_variable_set(:@parent, instance)
+    instance.instance_variable_set(:@fiber, Fiber.current)
+    instance
+  end
+  instance_variable_set(:@current, current)
+
+  def self.new(&block)
+    instance = allocate
+    instance.instance_variable_set(:@parent, @current)
+    instance.instance_variable_set(:@fiber, Fiber.new(&block))
+    @current = instance
+  end
+
+  def self.current
+    @current
+  end
+
+  attr_reader :parent
+
+  def switch(*args)
+    @fiber.transfer(*args)
+  end
+end
+
+def Greenlet(&block)
+  Greenlet.new &block
+end
+
+def process_commands(*args)
+  while true
+    line = ''
+    until line.end_with?("\n")
+      line += read_next_char()
+    end
+    if line == "quit\n"
+      puts "are you sure?"
+      if read_next_char() != 'y'
+        continue
+      end
+    end
+    process_command(line)
+  end
+end
+
+def process_command(cmd)
+  puts cmd
+end
+
+def event_keydown(key)
+  @g_processor.switch(key)
+end
+
+def read_next_char()
+  g_self = Greenlet.current
+  next_char = g_self.parent.switch()
+  return next_char
+end
+
+
+
+@g_processor = Greenlet(&method(:process_commands))
+@g_processor.switch([])
+
+
+event_keydown("h")
+event_keydown("e")
+event_keydown("l")
+event_keydown("l")
+event_keydown("o")
+event_keydown(" ")
+event_keydown("w")
+event_keydown("o")
+event_keydown("r")
+event_keydown("l")
+event_keydown("d")
+event_keydown("!")
+event_keydown("\n")