More work

src/ifcparse/IfcBaseClass.h

@@ -78,6 +78,21 @@ namespace IfcUtil {
 		virtual const IfcParse::entity& declaration() const = 0;
 
 		Argument* get(const std::string& name) const;
+
+		template <typename T>
+		T get_value_or(const std::string& name, const T& if_null) const {
+			auto arg = get(name);
+			if (arg->isNull()) {
+				return if_null;
+			} else {
+				return *arg;
+			}
+		}
+
+		template <typename T>
+		T get_value(const std::string& name) const {
+			return *get(name);
+		}
 	};
 
 	// TODO: Investigate whether these should be template classes instead

src/ifcparse/macros.h

@@ -27,7 +27,7 @@
 #define STRINGIFY_(x) #x
 #define STRINGIFY(x) STRINGIFY_(x)
 
-#define MAKE_INIT_FN__(a, b) init_ ## a ## b
+#define MAKE_INIT_FN__(a, b) init_ ## a ## _ ## b
 #define MAKE_INIT_FN_(a, b) MAKE_INIT_FN__(a, b)
 #define MAKE_INIT_FN(t) MAKE_INIT_FN_(t, IfcSchema)