unikernel/duniverse/cppo/test/lexical.cppo

@@ -0,0 +1,27 @@
+(* This test shows that the definition of BAR captures the original
+   definition of FOO, so even if FOO is redefined, the expansion of
+   BAR does not change. *)
+#define FOO "original definition"
+#define BAR FOO
+#undef  FOO
+#define FOO "new definition"
+FOO (* expands to "new definition" *)
+BAR (* expands to "original definition" *)
+
+(* This test shows that a formal parameter can shadow a previously
+   defined macro. *)
+#define F(FOO) FOO
+F(42) (* expands to 42 *)
+
+(* This test shows that two formal parameters can have the same
+   name. In that case, the second parameter shadows the first one. *)
+#define G(X, X) X+X
+G(42,23) (* expands to 23+23 *)
+
+(* This test shows that it is OK to pass an empty argument to a macro
+   that expects one parameter. This is interpreted as passing one
+   empty argument. *)
+#define expect(x) show(x)
+expect(42)
+expect("23")
+expect()