Decompose daemons.go; daemon dispatch becomes a table (step 7)

runDaemon's switch becomes gameData.daemonHandlers (the C d_func
function pointers restored as method expressions); stomach splits into
stomachFaint/stomachDigest; visuals gains visualMonsters. daemons.go
is complexity-clean. Behavior and RNG call order unchanged.

game/daemons.go

@@ -5,38 +5,14 @@ package game
 
 // runDaemon invokes the callback named by id (the call through d_func in C).
 func (g *RogueGame) runDaemon(id DaemonID, arg int) {
-	switch id {
+	h := g.data.daemonHandlers[id]
-	case DRollwand:
+	if h == nil {
-		g.rollwand(arg)
+		// Handlers are added to the table as their subsystems are
-	case DDoctor:
+		// ported; reaching one that isn't there is a porting bug.
-		g.doctor(arg)
-	case DStomach:
-		g.stomach(arg)
-	case DRunners:
-		g.runners(arg)
-	case DSwander:
-		g.swander(arg)
-	case DNohaste:
-		g.nohaste(arg)
-	case DUnconfuse:
-		g.unconfuse(arg)
-	case DUnsee:
-		g.unsee(arg)
-	case DSight:
-		g.sight(arg)
-	case DVisuals:
-		g.visuals(arg)
-	case DComeDown:
-		g.comeDown(arg)
-	case DLand:
-		g.land(arg)
-	case DTurnSee:
-		g.turnSee(arg != 0)
-	default:
-		// Callbacks are added to this switch as their subsystems are
-		// ported; reaching one that isn't here is a porting bug.
 		panic("daemon not yet ported")
 	}
+
+	h(g, arg)
 }
 
 // doctor is the healing daemon that restores hit points after rest
@@ -141,6 +117,24 @@ func (g *RogueGame) stomach(int) {
 
 	origHungry := p.HungryState
 	if p.FoodLeft <= 0 {
+		g.stomachFaint()
+	} else {
+		g.stomachDigest()
+	}
+
+	if p.HungryState != origHungry {
+		p.Flags.Clear(Awake)
+
+		g.Running = false
+		g.ToDeath = false
+		g.Count = 0
+	}
+}
+
+// stomachFaint starves and possibly faints an empty-stomached hero (the
+// no-food arm of daemons.c stomach).
+func (g *RogueGame) stomachFaint() {
+	p := &g.Player
 	if p.FoodLeft--; p.FoodLeft < -StarveTime {
 		g.death('s')
 	}
@@ -159,7 +153,12 @@ func (g *RogueGame) stomach(int) {
 	}
 
 	g.msg("%s", g.chooseStr("You freak out", "You faint"))
-	} else {
+}
+
+// stomachDigest burns food and reports growing hunger (the fed arm of
+// daemons.c stomach).
+func (g *RogueGame) stomachDigest() {
+	p := &g.Player
 	oldfood := p.FoodLeft
 
 	amulet := 0
@@ -185,15 +184,6 @@ func (g *RogueGame) stomach(int) {
 				"you are starting to get hungry"))
 		}
 	}
-	}
-
-	if p.HungryState != origHungry {
-		p.Flags.Clear(Awake)
-
-		g.Running = false
-		g.ToDeath = false
-		g.Count = 0
-	}
 }
 
 // comeDown takes the hero down off her acid trip (daemons.c come_down).
@@ -242,7 +232,6 @@ func (g *RogueGame) comeDown(int) {
 // visuals changes the characters for the player while hallucinating
 // (daemons.c visuals).
 func (g *RogueGame) visuals(int) {
-	p := &g.Player
 	if !g.After || (g.Running && g.Options.Jump) {
 		return
 	}
@@ -259,7 +248,13 @@ func (g *RogueGame) visuals(int) {
 	}
 
 	// change the monsters
-	seemonst := p.On(SenseMonsters)
+	g.visualMonsters()
+}
+
+// visualMonsters redraws the monsters through the hallucination (the
+// monster loop of daemons.c visuals).
+func (g *RogueGame) visualMonsters() {
+	seemonst := g.Player.On(SenseMonsters)
 
 	for _, tp := range g.Level.Monsters {
 		g.move(tp.Pos.Y, tp.Pos.X)

game/tables.go

@@ -151,6 +151,10 @@ type gameData struct {
 	// trapHandlers dispatches each sprung trap to its effect method:
 	// the cases of the move.c be_trapped switch.
 	trapHandlers [NumTrapTypes]func(g *RogueGame, tc Coord)
+
+	// daemonHandlers dispatches DaemonIDs to their callbacks: the C
+	// d_func function pointers (daemons.c / daemon.c).
+	daemonHandlers [DTurnSee + 1]func(g *RogueGame, arg int)
 }
 
 // ripWall is the repeated blank wall line of the tombstone art.
@@ -826,6 +830,24 @@ func newGameData() *gameData {
 			TrapRust:     (*RogueGame).trapRust,
 			TrapMystery:  (*RogueGame).trapMystery,
 		},
+
+		daemonHandlers: [DTurnSee + 1]func(*RogueGame, int){
+			DRollwand:  (*RogueGame).rollwand,
+			DDoctor:    (*RogueGame).doctor,
+			DStomach:   (*RogueGame).stomach,
+			DRunners:   (*RogueGame).runners,
+			DSwander:   (*RogueGame).swander,
+			DNohaste:   (*RogueGame).nohaste,
+			DUnconfuse: (*RogueGame).unconfuse,
+			DUnsee:     (*RogueGame).unsee,
+			DSight:     (*RogueGame).sight,
+			DVisuals:   (*RogueGame).visuals,
+			DComeDown:  (*RogueGame).comeDown,
+			DLand:      (*RogueGame).land,
+			DTurnSee: func(g *RogueGame, arg int) {
+				g.turnSee(arg != 0)
+			},
+		},
 	}
 }