From dc6a5751ed04ff15103c9852c8dc7427298b6945 Mon Sep 17 00:00:00 2001
From: "Eric S. Raymond" <esr@thyrsus.com>
Date: Tue, 13 Jun 2017 18:54:53 -0400
Subject: [PATCH] Magic-number elimination.

---
 advent.h |  4 +++-
 main.c   | 12 ++++++------
 misc.c   |  2 +-
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/advent.h b/advent.h
index 477b8b8..ee8e3fa 100644
--- a/advent.h
+++ b/advent.h
@@ -11,7 +11,8 @@
 #define MAXTRS		79
 #define MAXPARMS	25
 #define INVLIMIT	7
-#define INTRANSITIVE	-1	/* illegal object number */
+#define INTRANSITIVE	-1		/* illegal object number */
+#define SPECIALBASE	300		/* base umber of special rooms */
 
 typedef struct lcg_state
 {
@@ -146,6 +147,7 @@ extern int saveresume(FILE *, bool);
 #define GSTONE(OBJ)	((OBJ) == EMRALD || (OBJ) == RUBY || (OBJ) == AMBER || (OBJ) == SAPPH)
 #define FOREST(LOC)	((LOC) >= 145 && (LOC) <= 166)
 #define VOCWRD(LETTRS,SECT)	(VOCAB(MAKEWD(LETTRS),SECT))
+#define SPECIAL(LOC)	((LOC) > SPECIALBASE)
 
 /*  The following two functions were added to fix a bug (game.clock1 decremented
  *  while in forest).  They should probably be replaced by using another
diff --git a/main.c b/main.c
index 1f866d8..27a7a09 100644
--- a/main.c
+++ b/main.c
@@ -384,8 +384,8 @@ static bool dwarfmove(void)
 	if (kk != 0)
 	    do {
 		game.newloc=MOD(labs(TRAVEL[kk])/1000,1000);
-		/* Have we avoided a dwarf enciounter? */
-		bool avoided = (game.newloc > 300 ||
+		/* Have we avoided a dwarf encounter? */
+		bool avoided = (SPECIAL(game.newloc) ||
 				!INDEEP(game.newloc) ||
 				game.newloc == game.odloc[i] ||
 				(j > 1 && game.newloc == TK[j-1]) ||
@@ -529,7 +529,7 @@ static bool playermove(FILE *cmdin, token_t verb, int motion)
 	    for (;;) {
 		LL=MOD((labs(TRAVEL[KK])/1000),1000);
 		if (LL != motion) {
-		    if (LL <= 300) {
+		    if (!SPECIAL(LL)) {
 			if (FORCED(LL) && MOD((labs(TRAVEL[KEY[LL]])/1000),1000) == motion)
 			    K2=KK;
 		    }
@@ -607,7 +607,7 @@ static bool playermove(FILE *cmdin, token_t verb, int motion)
 	for (;;) {
 	    game.newloc=LL/1000;
 	    motion=MOD(game.newloc,100);
-	    if (game.newloc <= 300) {
+	    if (!SPECIAL(game.newloc)) {
 		if (game.newloc <= 100) {
 		    if (game.newloc == 0 || PCT(game.newloc))
 			break;
@@ -628,10 +628,10 @@ static bool playermove(FILE *cmdin, token_t verb, int motion)
 	}
 
 	game.newloc=MOD(LL,1000);
-	if (game.newloc <= 300)
+	if (!SPECIAL(game.newloc))
 	    return true;
 	if (game.newloc <= 500) {
-	    game.newloc=game.newloc-300;
+	    game.newloc=game.newloc-SPECIALBASE;
 	    switch (game.newloc)
 	    {
 	    case 1:
diff --git a/misc.c b/misc.c
index c47ce1d..6f33146 100644
--- a/misc.c
+++ b/misc.c
@@ -367,7 +367,7 @@ void MOVE(long object, long where)
 	from=game.fixed[object-NOBJECTS];
     else
 	from=game.place[object];
-    if (from > 0 && from <= 300)
+    if (from > 0 && !SPECIAL(from))
 	CARRY(object,from);
     DROP(object,where);
 }
-- 
2.31.1