From 6fdacb0759144b13099867b590a548db7df7ae01 Mon Sep 17 00:00:00 2001
From: Peter Nelson <peter1138@openttd.org>
Date: Wed, 1 Oct 2025 21:54:40 +0100
Subject: [PATCH] Codechange: Use find/find_if to search for rail/road types by
 label.

Replaces manual loops.
---
 src/rail.cpp | 16 ++++++----------
 src/road.cpp | 16 ++++++----------
 2 files changed, 12 insertions(+), 20 deletions(-)

diff --git a/src/rail.cpp b/src/rail.cpp
index 7e7174fef2..b977c1c963 100644
--- a/src/rail.cpp
+++ b/src/rail.cpp
@@ -194,20 +194,16 @@ RailTypes GetRailTypes(bool introduces)
  */
 RailType GetRailTypeByLabel(RailTypeLabel label, bool allow_alternate_labels)
 {
+	extern RailTypeInfo _railtypes[RAILTYPE_END];
 	if (label == 0) return INVALID_RAILTYPE;
 
-	/* Loop through each rail type until the label is found */
-	for (RailType r = RAILTYPE_BEGIN; r != RAILTYPE_END; r++) {
-		const RailTypeInfo *rti = GetRailTypeInfo(r);
-		if (rti->label == label) return r;
+	auto it = std::ranges::find(_railtypes, label, &RailTypeInfo::label);
+	if (it == std::end(_railtypes) && allow_alternate_labels) {
+		/* Test if any rail type defines the label as an alternate. */
+		it = std::ranges::find_if(_railtypes, [label](const RailTypeInfo &rti) { return rti.alternate_labels.contains(label); });
 	}
 
-	if (allow_alternate_labels) {
-		/* Test if any rail type defines the label as an alternate. */
-		for (RailType r = RAILTYPE_BEGIN; r != RAILTYPE_END; r++) {
-			if (GetRailTypeInfo(r)->alternate_labels.contains(label)) return r;
-		}
-	}
+	if (it != std::end(_railtypes)) return it->Index();
 
 	/* No matching label was found, so it is invalid */
 	return INVALID_RAILTYPE;
diff --git a/src/road.cpp b/src/road.cpp
index 590abfa07c..18478e9598 100644
--- a/src/road.cpp
+++ b/src/road.cpp
@@ -264,20 +264,16 @@ RoadTypes GetRoadTypes(bool introduces)
  */
 RoadType GetRoadTypeByLabel(RoadTypeLabel label, bool allow_alternate_labels)
 {
+	extern RoadTypeInfo _roadtypes[ROADTYPE_END];
 	if (label == 0) return INVALID_ROADTYPE;
 
-	/* Loop through each road type until the label is found */
-	for (RoadType r = ROADTYPE_BEGIN; r != ROADTYPE_END; r++) {
-		const RoadTypeInfo *rti = GetRoadTypeInfo(r);
-		if (rti->label == label) return r;
+	auto it = std::ranges::find(_roadtypes, label, &RoadTypeInfo::label);
+	if (it == std::end(_roadtypes) && allow_alternate_labels) {
+		/* Test if any road type defines the label as an alternate. */
+		it = std::ranges::find_if(_roadtypes, [label](const RoadTypeInfo &rti) { return rti.alternate_labels.contains(label); });
 	}
 
-	if (allow_alternate_labels) {
-		/* Test if any road type defines the label as an alternate. */
-		for (RoadType r = ROADTYPE_BEGIN; r != ROADTYPE_END; r++) {
-			if (GetRoadTypeInfo(r)->alternate_labels.contains(label)) return r;
-		}
-	}
+	if (it != std::end(_roadtypes)) return it->Index();
 
 	/* No matching label was found, so it is invalid */
 	return INVALID_ROADTYPE;