Separate out node type as an enumeration.

parser.h

@@ -3,11 +3,8 @@
 
 #include "./lib.h"
 
-typedef struct
+typedef enum
 {
-  size_t col, row;
-  enum
-  {
   NEXT = 0,
   PREV,
   INC,
@@ -16,7 +13,12 @@ typedef struct
   READ,
   LIN,
   LOUT
-  } type;
+} node_type_t;
+
+typedef struct
+{
+  size_t col, row;
+  node_type_t type;
   int loop_ref;
 } node_t;