imported kevin's three token-parser choices into core.clj

src/hs_robotwar/core.clj

@@ -63,18 +63,36 @@
 
 (def return-err (ignoring-args-thunk "Invalid word or symbol"))
 
+(def parser-priority
+ [[registers  :register]
+  [commands   :command]
+  [str->int   :number]
+  [valid-word :label]
+  [return-err :error]])
+
 (defn parse-token
   "takes a single token and adds the appropriate metadata"
-  [{token-str :token-str, pos :pos}]
+  [{:keys [token-str pos]}]
   (some
     (fn [[parser token-type]]
       (when-let [token-val (parser token-str)]
         {:val token-val, :type token-type, :pos pos}))
-    [[registers  :register]
-     [commands   :command]
-     [str->int   :number]
-     [valid-word :label]
-     [return-err :error]]))
+    parser-priority))
+
+(defn parse-token-2
+ "takes a single token and adds the appropriate metadata"
+ [{:keys [token-str pos]}]
+ (first (for [[parser token-type] parser-priority 
+              :let [token-val (parser token-str)] 
+              :when token-val]
+         {:val token-val, :type token-type, :pos pos})))
+
+(defn parse-token-3
+ "takes a single token and adds the appropriate metadata"
+ [{:keys [token-str pos]}]
+ (some identity (for [[parser token-type] parser-priority]
+                 (when-let [token-val (parser token-str)]
+                  {:val token-val, :type token-type, :pos pos}))))
 
 (def value-type? #{:number :register})