1 files changed, 67 insertions, 0 deletions
diff --git a/src/mbgl/util/literal.hpp b/src/mbgl/util/literal.hpp
new file mode 100644
index 0000000000..d4fec49b35
--- /dev/null
+++ b/src/mbgl/util/literal.hpp
@@ -0,0 +1,67 @@
+#pragma once
+
+#include <utility>
+#include <cstddef>
+
+namespace mbgl {
+
+// Using structs instead of constexpr templates because GCC 4.9 doesn't support these yet.
+
+template <char... Cs>
+struct string_literal {
+    static constexpr const char chars[] = { Cs..., 0 };
+
+    static constexpr const char* value() {
+        return chars;
+    }
+};
+
+template <char... Cs>
+constexpr const char string_literal<Cs...>::chars[];
+
+namespace detail {
+
+using string_fn = const char* (*)();
+
+template <string_fn name, std::size_t... Is>
+string_literal<name()[Is]...> to_string_literal(std::index_sequence<Is...>);
+
+constexpr std::size_t string_length(const char* const str, std::size_t len = 0) {
+    return str[0] ? string_length(str + 1, len + 1) : len;
+}
+
+template <class...>
+struct concat_literals;
+
+template <>
+struct concat_literals<> {
+    static constexpr auto value() {
+        return "";
+    }
+};
+
+template <char... As, char... Bs, class... Rest>
+struct concat_literals<string_literal<As...>, string_literal<Bs...>, Rest...> {
+    static constexpr auto value() {
+        return concat_literals<string_literal<As..., Bs...>, Rest...>::value();
+    }
+};
+
+template <char... Cs>
+struct concat_literals<string_literal<Cs...>> {
+    static constexpr auto value() {
+        return string_literal<Cs...>::value();
+    }
+};
+
+} // namespace detail
+
+template <detail::string_fn... str>
+struct concat_literals {
+    static constexpr auto value() {
+        return detail::concat_literals<decltype(detail::to_string_literal<str>(
+            std::make_index_sequence<detail::string_length(str())>()))...>::value();
+    }
+};
+
+} // namespace mbgl