Codechange: Use comparator struct to sort cargo ID by predefined sort order.

This allows reuse of the comparator where a typename is used instead.

src/cargotype.h

@@ -204,4 +204,9 @@ static inline bool IsCargoInClass(CargoID c, CargoClass cc)
 
 using SetCargoBitIterator = SetBitIterator<CargoID, CargoTypes>;
 
+/** Comparator to sort CargoID by according to desired order. */
+struct CargoIDComparator {
+	bool operator() (const CargoID &lhs, const CargoID &rhs) const { return _sorted_cargo_types[lhs] < _sorted_cargo_types[rhs]; }
+};
+
 #endif /* CARGOTYPE_H */

src/industry_gui.cpp

@@ -1920,11 +1920,6 @@ enum CargoesFieldType {
 
 static const uint MAX_CARGOES = 16; ///< Maximum number of cargoes carried in a #CFT_CARGO field in #CargoesField.
 
-static bool CargoIDSorter(const CargoID &a, const CargoID &b)
-{
-	return _sorted_cargo_types[a] < _sorted_cargo_types[b];
-}
-
 /** Data about a single field in the #IndustryCargoesWindow panel. */
 struct CargoesField {
 	static int vert_inter_industry_space;
@@ -2054,7 +2049,8 @@ struct CargoesField {
 			}
 		}
 		this->u.cargo.num_cargoes = (count < 0) ? static_cast<uint8_t>(insert - std::begin(this->u.cargo.vertical_cargoes)) : count;
-		std::sort(std::begin(this->u.cargo.vertical_cargoes), insert, &CargoIDSorter);
+		CargoIDComparator comparator;
+		std::sort(std::begin(this->u.cargo.vertical_cargoes), insert, comparator);
 		std::fill(insert, std::end(this->u.cargo.vertical_cargoes), CT_INVALID);
 		this->u.cargo.top_end = top_end;
 		this->u.cargo.bottom_end = bottom_end;