Fix style application

internal/system/style.go

@@ -5,20 +5,21 @@ import "git.tebibyte.media/tomo/tomo"
 type styleApplicator struct {
 	style *tomo.Style
 	role  tomo.Role
-	rules []*tomo.Rule
+	rules []tomo.Rule
 }
 
 func (this *styleApplicator) apply (box anyBox) {
 	if box.Role() != this.role {
+		this.role = box.Role()
 		// the role has changed, so re-cache the list of rules
-		this.rules = make([]*tomo.Rule, 0, 4)
+		this.rules = nil
 		for _, rule := range this.style.Rules {
 			role := box.Role()
 			// blank fields match anything
 			if rule.Role.Package == "" { role.Package = "" }
 			if rule.Role.Object  == "" { role.Object  = "" }
 			if rule.Role == role {
-				this.rules = append(this.rules, &rule)
+				this.rules = append(this.rules, rule)
 			}
 		}
 	}
@@ -27,12 +28,10 @@ func (this *styleApplicator) apply (box anyBox) {
 	attrs := make(tomo.AttrSet)
 	for _, rule := range this.rules {
 		satisifed := true
-		if rule.Tags != nil {
-			for _, tag := range rule.Tags {
-				if !box.Tag(tag) {
-					satisifed = false
-					break
-				}
+		for _, tag := range rule.Tags {
+			if !box.Tag(tag) {
+				satisifed = false
+				break
 			}
 		}