validation: checks: named dummy types for readability

validation/src/check.rs

@@ -302,8 +302,12 @@ pub struct MapInfoOwned{
 	pub game_id:GameID,
 }
 
+// Named dummy types for readability
+struct Exists;
+struct Absent;
+
 // crazy!
-pub struct MapCheck<'a>{
+struct MapCheck<'a>{
 	// === METADATA CHECKS ===
 	// The root must be of class Model
 	model_class:StringCheck<'a,(),&'static str>,
@@ -321,7 +325,7 @@ pub struct MapCheck<'a>{
 
 	// === MODE CHECKS ===
 	// MapStart must exist
-	mapstart:Result<(),()>,
+	mapstart:Result<Exists,Absent>,
 	// No duplicate map starts (including bonuses)
 	mode_start_counts:DuplicateCheck<ModeID,Vec<&'a str>>,
 	// At least one finish zone for each start zone, and no finishes with no start
@@ -329,7 +333,7 @@ pub struct MapCheck<'a>{
 	// Check for dangling MapAnticheat zones (no associated MapStart)
 	mode_anticheat_counts:SetDifferenceCheck<SetDifferenceCheckContextAllowNone<ModeID,Vec<&'a str>>>,
 	// Spawn1 must exist
-	spawn1:Result<(),()>,
+	spawn1:Result<Exists,Absent>,
 	// Check for dangling Teleport# (no associated Spawn#)
 	teleport_counts:SetDifferenceCheck<SetDifferenceCheckContextAllowNone<SpawnID,Vec<&'a str>>>,
 	// No duplicate Spawn#
@@ -371,16 +375,16 @@ impl<'a> ModelInfo<'a>{
 
 		// MapStart must exist
 		let mapstart=if self.counts.mode_start_counts.contains_key(&ModeID::MAIN){
-			Ok(())
+			Ok(Exists)
 		}else{
-			Err(())
+			Err(Absent)
 		};
 
 		// Spawn1 must exist
 		let spawn1=if self.counts.spawn_counts.contains_key(&SpawnID::FIRST){
-			Ok(())
+			Ok(Exists)
 		}else{
-			Err(())
+			Err(Absent)
 		};
 
 		// Check that at least one finish zone exists for each start zone.
@@ -440,11 +444,11 @@ impl MapCheck<'_>{
 				display_name:Ok(Ok(StringCheck(Ok(display_name)))),
 				creator:Ok(Ok(creator)),
 				game_id:Ok(game_id),
-				mapstart:Ok(()),
+				mapstart:Ok(Exists),
 				mode_start_counts:DuplicateCheck(Ok(())),
 				mode_finish_counts:SetDifferenceCheck(Ok(())),
 				mode_anticheat_counts:SetDifferenceCheck(Ok(())),
-				spawn1:Ok(()),
+				spawn1:Ok(Exists),
 				teleport_counts:SetDifferenceCheck(Ok(())),
 				spawn_counts:DuplicateCheck(Ok(())),
 				wormhole_in_counts:SetDifferenceCheck(Ok(())),
@@ -511,7 +515,7 @@ impl std::fmt::Display for MapCheck<'_>{
 		if let Err(_parse_game_id_error)=&self.game_id{
 			writeln!(f,"Model name must be prefixed with bhop_ surf_ or flytrials_")?;
 		}
-		if let Err(())=&self.mapstart{
+		if let Err(Absent)=&self.mapstart{
 			writeln!(f,"Model has no MapStart")?;
 		}
 		if let DuplicateCheck(Err(DuplicateCheckContext(context)))=&self.mode_start_counts{
@@ -551,7 +555,7 @@ impl std::fmt::Display for MapCheck<'_>{
 				writeln!(f)?;
 			}
 		}
-		if let Err(())=&self.spawn1{
+		if let Err(Absent)=&self.spawn1{
 			writeln!(f,"Model has no Spawn1")?;
 		}
 		if let SetDifferenceCheck(Err(context))=&self.teleport_counts{