changed tick-duration so it's a parameter passed into tick-world

src/robotwar/core.clj

@@ -8,7 +8,7 @@
 
 (def world 
   (world/init-world 256.0 256.0 [test-programs/multi-use-program]))
-(def worlds (world/iterate-worlds world))
+(def worlds (world/iterate-worlds world 1.0))
 
 (def robots (:robots world))
 (def robot (robots 0))

src/robotwar/world.clj

@@ -2,12 +2,6 @@
   (:use [clojure.string :only [join]])
   (:require [robotwar.robot :as robot]))
 
-
-(def TICK_DURATION 1.0)
-
-
-; TODO: pass in tick-duration to world from somewhere else.
-;
 (defn init-world
   "initialize all the variables for a robot world."
   [width height programs]
@@ -31,15 +25,15 @@
   (where each robot gets to go) rather than just a stream of worlds, one for 
   each robot. Because otherwise, do we step the shells after every 
   single robot has their turn?"
-  [{:keys [robots robot-idx] :as world}]
-  (assoc (robot/step-robot (robots robot-idx) world TICK_DURATION)
+  [{:keys [robots robot-idx] :as world} tick-duration]
+  (assoc (robot/step-robot (robots robot-idx) world tick-duration)
          :robot-idx
          (mod (inc robot-idx) (count robots))))
 
 (defn iterate-worlds
   "convenience function for creating a sequence of worlds"
-  [world]
-  (iterate tick-world world))
+  [world tick-duration]
+  (iterate #(tick-world % tick-duration) world))
   
 (defn get-world
   "convenience function for identifying a world in a sequence of worlds

test/robotwar/brain_test.clj

@@ -9,7 +9,7 @@
 (def initial-world 
   (world/init-world 256.0 256.0 [test-programs/multi-use-program]))
 
-(def worlds (iterate world/tick-world initial-world))
+(def worlds (world/iterate-worlds initial-world 1.0))
 
 (deftest branching-test
   (testing "comparison statement should cause jump in instr-ptr"

test/robotwar/robot_test.clj

@@ -37,6 +37,3 @@
    robotwar.core=>
 
 
-   TODO: Change the function so that the TICK_DURATION comes from the world, not from 
-   a constant in the file. This way, we can easily set it to 1 for tests, and adjust it
-   appropriately for actual game play.