7 files changed, 25 insertions, 28 deletions
diff --git a/src/ai/ai.hpp b/src/ai/ai.hpp
index 0485cabae..2653e66ae 100644
--- a/src/ai/ai.hpp
+++ b/src/ai/ai.hpp
@@ -7,11 +7,9 @@
 
 #include "api/ai_event_types.hpp"
 #include "../date_type.h"
+#include "../core/string_compare_type.hpp"
 
-#ifndef AI_CONFIG_HPP
-struct ltstr { bool operator()(const char *s1, const char *s2) const { return strcmp(s1, s2) < 0; } };
-#endif /* AI_CONFIG_HPP */
-typedef std::map<const char *, class AIInfo *, ltstr> AIInfoList;
+typedef std::map<const char *, class AIInfo *, StringCompare> AIInfoList;
 
 
 void CcAI(bool success, TileIndex tile, uint32 p1, uint32 p2);
diff --git a/src/ai/ai_config.hpp b/src/ai/ai_config.hpp
index 39b680f1c..ca8b05a39 100644
--- a/src/ai/ai_config.hpp
+++ b/src/ai/ai_config.hpp
@@ -7,14 +7,11 @@
 
 #include <map>
 #include "ai_info.hpp"
-
-#ifndef AI_HPP
-struct ltstr { bool operator()(const char *s1, const char *s2) const { return strcmp(s1, s2) < 0; } };
-#endif /* AI_HPP */
+#include "../core/string_compare_type.hpp"
 
 class AIConfig {
 private:
-	typedef std::map<const char *, int, ltstr> SettingValueList;
+	typedef std::map<const char *, int, StringCompare> SettingValueList;
 
 public:
 	AIConfig() :
diff --git a/src/ai/ai_scanner.hpp b/src/ai/ai_scanner.hpp
index 3bfa27bfc..9818288bb 100644
--- a/src/ai/ai_scanner.hpp
+++ b/src/ai/ai_scanner.hpp
@@ -5,6 +5,7 @@
 #ifndef AI_SCANNER_HPP
 #define AI_SCANNER_HPP
 
+#include "../core/string_compare_type.hpp"
 #include <map>
 
 class AIScanner {
@@ -73,7 +74,7 @@ public:
   bool HasAI(const struct ContentInfo *ci, bool md5sum);
 #endif
 private:
-	typedef std::map<const char *, class AILibrary *, ltstr> AILibraryList;
+	typedef std::map<const char *, class AILibrary *, StringCompare> AILibraryList;
 
 	/**
 	 * Scan the AI dir for scripts.
diff --git a/src/ai/api/ai_controller.hpp b/src/ai/api/ai_controller.hpp
index 1f1df743e..d4e2bd6dc 100644
--- a/src/ai/api/ai_controller.hpp
+++ b/src/ai/api/ai_controller.hpp
@@ -5,10 +5,8 @@
 #ifndef AI_CONTROLLER_HPP
 #define AI_CONTROLLER_HPP
 
+#include "../../core/string_compare_type.hpp"
 #include <map>
-#ifndef AI_HPP
-struct ltstr { bool operator()(const char *s1, const char *s2) const { return strcmp(s1, s2) < 0; } };
-#endif /* AI_HPP */
 
 /**
  * The Controller, the class each AI should extend. It creates the AI, makes
@@ -85,7 +83,7 @@ public:
 	static void Print(bool error_msg, const char *message);
 
 private:
-	typedef std::map<const char *, const char *, ltstr> LoadedLibraryList;
+	typedef std::map<const char *, const char *, StringCompare> LoadedLibraryList;
 
 	uint ticks;
 	LoadedLibraryList loaded_library;
diff --git a/src/blitter/factory.hpp b/src/blitter/factory.hpp
index 4f7a4b108..a1ab6dc6e 100644
--- a/src/blitter/factory.hpp
+++ b/src/blitter/factory.hpp
@@ -8,6 +8,7 @@
 #include "base.hpp"
 #include "../debug.h"
 #include "../string_func.h"
+#include "../core/string_compare_type.hpp"
 #include <map>
 
 #if defined(WITH_COCOA)
@@ -21,13 +22,6 @@ class BlitterFactoryBase {
 private:
 	const char *name;
 
-	struct StringCompare {
-		bool operator () (const char *a, const char *b) const
-		{
-			return strcmp(a, b) < 0;
-		}
-	};
-
 	typedef std::map<const char *, BlitterFactoryBase *, StringCompare> Blitters;
 
 	static Blitters &GetBlitters()
diff --git a/src/core/string_compare_type.hpp b/src/core/string_compare_type.hpp
new file mode 100644
index 000000000..c4bb71819
--- /dev/null
+++ b/src/core/string_compare_type.hpp
@@ -0,0 +1,15 @@
+/* $Id$ */
+
+/** @file string_compare_type.hpp Comparator class for "const char *" so it can be used as a key for std::map */
+
+#ifndef STRING_COMPARE_TYPE_HPP
+#define STRING_COMPARE_TYPE_HPP
+
+struct StringCompare {
+	bool operator () (const char *a, const char *b) const
+	{
+		return strcmp(a, b) < 0;
+	}
+};
+
+#endif /* STRING_COMPARE_TYPE_HPP */
diff --git a/src/driver.h b/src/driver.h
index 61fede9c4..b2a359b97 100644
--- a/src/driver.h
+++ b/src/driver.h
@@ -6,6 +6,7 @@
 #define DRIVER_H
 
 #include "core/enum_type.hpp"
+#include "core/string_compare_type.hpp"
 #include "string_func.h"
 #include <map>
 
@@ -39,13 +40,6 @@ private:
 	const char *name;
 	int priority;
 
-	struct StringCompare {
-		bool operator () (const char *a, const char *b) const
-		{
-			return strcmp(a, b) < 0;
-		}
-	};
-
 	typedef std::map<const char *, DriverFactoryBase *, StringCompare> Drivers;
 
 	static Drivers &GetDrivers()