improve README

README.md

@@ -65,4 +65,8 @@ class ExampleGenerator : Cpp2BeefGenerator, this(Span<char8*> args)
 	
 	// There are functions you can override, but these are the most common
 }
+
+// Create a single header file that includes all other header files and then call Generate once
+// This is significanly faster than calling Generate for each header file because of header guards
+scope ExampleGenerator(char8*[?]("--language=c", "-DSOMETHING")).Generate("example.h");
 ```