(I_NONE, I_CIVIL, I_MILIT, I_SHELL, I_GUN, I_PETROL, I_IRON, I_DUST,

I_BAR, I_FOOD, I_OIL, I_LCM, I_HCM, I_UW, I_RAD, I_MAX): Turn macros
into enumeration constants.
(i_type): New.  Use where appropriate.  No functional changes, except
that I_NONE is now catched properly in a few places.

src/lib/commands/thre.c

@@ -55,7 +55,7 @@ thre(void)
     struct ichrstr *ip;
     s_char *p;
     int thresh;
-    int type;
+    i_type type;
     s_char prompt[128];
     s_char buf[128];