Reland "More tests for Union & Intersect"

src/types.h

Index: src/types.h
diff --git a/src/types.h b/src/types.h
index da63e5fd56de4803ba9ab8343dc4a20019b81a1f..3a3bc3bd08ba392790fff82d2e5cb5192fa233c8 100644
--- a/src/types.h
+++ b/src/types.h
@@ -101,11 +101,11 @@ namespace internal {
 // PROPERTIES
 //
 // Various formal properties hold for constructors, operators, and predicates
-// over types. For example, constructors are injective, subtyping is a partial
-// order, and union and intersection satisfy the usual algebraic properties.
+// over types. For example, constructors are injective, subtyping is a complete
+// partial order, union and intersection satisfy the usual algebraic properties.
 //
 // See test/cctest/test-types.cc for a comprehensive executable specification,
-// especially with respect to the proeprties of the more exotic 'temporal'
+// especially with respect to the properties of the more exotic 'temporal'
 // constructors and predicates (those prefixed 'Now').
 //
 // IMPLEMENTATION