Added logging; simulation ALMOST runs

src/the_great_game/gossip/gossip.clj

@@ -40,6 +40,24 @@
                #(= (:location %) (:location g))
                (vals (:gossips world))))))}})))
 
+(defn move-gossip
+  "Return a world like this `world` but with this `gossip` moved to this
+  `new-location`. Many gossips are essentially shadow-records of agents of
+  other types, and the movement if the gossip should be controlled by the
+  run function of the type of the record they shadow. The [[#run]] function
+  below does NOT call this function."
+  [gossip world new-location]
+  (let [id (cond
+            (map? gossip)
+            (:id (-> world :gossipe gossip)
+            (keyword? gossip)
+            gossip))]
+  (deep-merge
+    world
+    {:gossips
+     {id
+      {:location new-location}}})))
+
 (defn run
   "Return a world like this `world`, with news items exchanged between gossip
   agents."

src/the_great_game/merchants/markets.clj

@@ -1,6 +1,7 @@
 (ns the-great-game.merchants.markets
   "Adjusting quantities and prices in markets."
-  (:require [the-great-game.utils :refer [deep-merge]]
+  (:require [taoensso.timbre :as l :refer [info error]]
+            [the-great-game.utils :refer [deep-merge]]
             [the-great-game.world.world :refer [actual-price default-world]]))
 
 (defn new-price
@@ -38,12 +39,15 @@
                     (> su st)
                     (- su st)
                     true 0)
-        price (new-price p st su d)]
+        n (new-price p st su d)]
+    (if
+      (not (= p n))
+      (l/info "Price of " commodity " at " id " has changed from " (float p) " to " (float n)))
     {:cities {id
               {:stock
                {commodity (+ (- st decrement) increment)}
                :prices
-               {commodity price}}}}))
+               {commodity n}}}}))
 
 
 (defn update-markets

src/the_great_game/merchants/merchants.clj

@@ -2,6 +2,7 @@
   "Trade planning for merchants, primarily."
   (:require [taoensso.timbre :as l :refer [info error]]
             [the-great-game.utils :refer [deep-merge]]
+            [the-great-game.gossip.gossip :refer [move-gossip]]
             [the-great-game.world.routes :refer [find-route]]
             [the-great-game.world.world :refer [actual-price default-world]]))
 
@@ -309,16 +310,19 @@
              :cash (+ (:cash market) p)}}})
         ;; if no plan, then if at home stay put
         (= (:location m) (:home m))
-        {}
+        (do
+          (l/info "Merchant " id " remains at home in " location)
+          {})
         ;; else move towards home
         true
         (let [route (find-route world location (:home m))
               next-location (nth route 1)]
           (l/info "No trade possible at " location "; merchant " id " moves to " next-location)
-          {:merchants
+          (merge
+            {:merchants
            {id
-            {:location next-location}}})))))
-
+            {:location next-location}}}
+            (move-gossip id world next-location)))))))
 
 (defn re-plan
   "Having failed to sell a cargo at current location, re-plan a route to
@@ -338,7 +342,6 @@
        {id
         {:plan plan}}})))
 
-
 (defn sell-and-buy
   "Return a new world like this `world`, in which this `merchant` has sold
   their current stock in their current location, and planned a new trade, and
@@ -381,7 +384,6 @@
       ;; else
       (re-plan merchant world))))
 
-
 (defn move-merchant
   "Handle general en route movement of this `merchant` in this `world`."
   [merchant world]
@@ -396,18 +398,23 @@
         next-location (if plan
                         (nth 1 (find-route world (:location m) (:destination plan)))
                         (:location m))]
-    (l/info "Merchant " id " at " (:location m))
-    (cond at-destination?
-          (sell-and-buy merchant world plan)
-          (nil? (:plan m))
-          (plan-and-buy merchant world)
-          true
-          {:merchants
-           {id
-            {:id id
-             :location next-location
-             :known-prices (add-known-prices m world)}}})))
-
+    (l/info "Merchant " id " has moved from " (:location m) " to " next-location)
+    (cond
+      ;; if the merchant is at the destination of their current plan
+      ;; sell all cargo and repurchase.
+      at-destination?
+      (sell-and-buy merchant world plan)
+      ;; if they don't have a plan, seek to create one
+      (nil? (:plan m))
+      (plan-and-buy merchant world)
+      ;; otherwise, move one step towards their destination
+      true
+      (deep-merge
+        {:merchants
+         {id
+          {:location next-location
+           :known-prices (add-known-prices m world)}}}
+        (move-gossip id world next-location)))))
 
 (defn run
   "Return a world like this `world`, but with each merchant moved."

src/the_great_game/world/world.clj

@@ -185,6 +185,6 @@
 (defn run
   "Return a world like this `world` with only the `:date` value updated
   (incremented by one). For running other aspects of the simulation, see
-  [[the-great-game.world.run#var-run]]."
+  [[the-great-game.world.run]]."
   [world]
   (assoc world :date (inc (or (:date world) 0))))