[flang] Remove dead code.

Original-commit: flang-compiler/f18@a85e16c704422f42c0811c51bd4e668b407d11c6
Reviewed-on: https://github.com/flang-compiler/f18/pull/66
Tree-same-pre-rewrite: false

diff --git a/flang/lib/parser/idioms.h b/flang/lib/parser/idioms.h
index a22c0def8d455e9b0e7b810ae80c7f360abb0fbb..b6d6d62d0684ce51f3859addd2e2846e749a0e6a 100644 (file)
--- a/flang/lib/parser/idioms.h
+++ b/flang/lib/parser/idioms.h
@@ -30,8 +30,8 @@ template<typename A>
 struct is_trivially_copy_constructible<optional<list<A>>> : false_type {};
 }  // namespace std
 
-using namespace std::literals::string_literals;  // enable "this is a
-                                                 // std::string"s
+// enable "this is a std::string"s with the 's' suffix
+using namespace std::literals::string_literals;
 
 namespace Fortran {
 namespace parser {
@@ -73,11 +73,6 @@ template<typename A> bool operator!(const std::optional<A> &x) {
           false))
 #endif
 
-// To make error messages more informative, wrap some type information
-// around a false compile-time value, e.g.
-//   static_assert(BadType<T>::value, "no case for type");
-template<typename A> struct BadType : std::false_type {};
-
 // User-defined type traits that default to false:
 // Invoke CLASS_TRAIT(traitName) to define a trait, then put
 //   using traitName = std::true_type;  (or false_type)