@define foo(e)
{
	switch(e){
	@match #this(#[ a, b ], #that):
		printf("matched %a %a\n", a, b);
		break;
	default:
		printf("no match\n");
		break;
	} 
}

foo(#this(#[ #a, #b ], #that));
foo(#this(#[ #a ], #that));