✨ Add name_for

docs/ct_string.adoc

@@ -145,6 +145,21 @@ static_assert(stdx::constant_name_of_v<S> == "name"_ctst>);
 using N = stdx::constant_name_of_t<S>; // stdx::cts_t<"name">
 ----
 
+==== `name_for` and `constant_name_for`
+
+When you don't know whether or not a type has a name, `name_for` will return
+either its name or a `ct_string` of its type. `constant_name_for` will return
+the same content as a `cts_t`.
+
+[source,cpp]
+----
+static_assert(stdx::name_for<S>() == "name"_cts);
+static_assert(stdx::name_for<int>() == "int"_cts);
+
+static_assert(stdx::constant_name_for<S>() == "name"_ctst);
+static_assert(stdx::constant_name_for<int>() == "int"_ctst);
+----
+
 ==== `matching_name` and `same_name`
 
 Use the `matching_name` concept to check whether a type's name matches a string.

include/stdx/ct_string.hpp

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <stdx/compiler.hpp>
+#include <stdx/ct_conversions.hpp>
 #include <stdx/type_traits.hpp>
 #include <stdx/utility.hpp>
 
@@ -222,5 +223,18 @@ using same_name_t = std::bool_constant<same_name<T, U>>;
 template <named T> struct same_name_q {
     template <named U> using fn = same_name_t<T, U>;
 };
+
+template <typename T> consteval auto name_for() {
+    if constexpr (named<T>) {
+        return name_of_v<T>;
+    } else {
+        constexpr auto name = type_as_string<T>();
+        return ct_string<name.size() + 1>{name};
+    }
+}
+
+template <typename T> consteval auto constant_name_for() {
+    return cts_t<name_for<T>()>{};
+}
 } // namespace v1
 } // namespace stdx

test/ct_string.cpp

@@ -212,3 +212,12 @@ TEST_CASE("named object", "[ct_string]") {
     STATIC_CHECK(not stdx::same_name_t<T, U>::value);
     STATIC_CHECK(not stdx::same_name_q<T>::template fn<U>::value);
 }
+
+TEST_CASE("name or type fallback", "[ct_string]") {
+    using namespace stdx::ct_string_literals;
+    using T = stdx::with_name<"test">;
+    STATIC_CHECK(stdx::name_for<T>() == "test"_cts);
+    STATIC_CHECK(stdx::name_for<int>() == "int"_cts);
+    STATIC_CHECK(stdx::constant_name_for<T>() == "test"_ctst);
+    STATIC_CHECK(stdx::constant_name_for<int>() == "int"_ctst);
+}