Revert "remove external libraries from main branch"protocol-modeling

This reverts commit 0558244645611f314f47e0fa427f7323ce253eaf.

1 files changed, 13 insertions, 0 deletions

diff --git a/include/lib/modernjson/detail/meta/void_t.hpp b/include/lib/modernjson/detail/meta/void_t.hpp
new file mode 100644
index 0000000..a256f85
--- /dev/null
+++ b/include/lib/modernjson/detail/meta/void_t.hpp
@@ -0,0 +1,13 @@
+#pragma once
+
+namespace nlohmann
+{
+namespace detail
+{
+template <typename ...Ts> struct make_void
+{
+    using type = void;
+};
+template <typename ...Ts> using void_t = typename make_void<Ts...>::type;
+} // namespace detail
+}  // namespace nlohmann