1 files changed, 58 insertions, 0 deletions
diff --git a/extra/guile/scm/detail/convert.hpp b/extra/guile/scm/detail/convert.hpp
new file mode 100644
index 000000000000..4c87ff185669
--- /dev/null
+++ b/extra/guile/scm/detail/convert.hpp
@@ -0,0 +1,58 @@
+//
+// immer: immutable data structures for C++
+// Copyright (C) 2016, 2017, 2018 Juan Pedro Bolivar Puente
+//
+// This software is distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE or copy at http://boost.org/LICENSE_1_0.txt
+//
+
+#pragma once
+
+#include <scm/detail/util.hpp>
+
+#include <cstdint>
+#include <type_traits>
+#include <utility>
+
+#include <libguile.h>
+
+namespace scm {
+namespace detail {
+
+template <typename T, typename Enable=void>
+struct convert;
+
+template <typename T>
+auto to_scm(T&& v)
+    -> SCM_DECLTYPE_RETURN(
+        convert<std::decay_t<T>>::to_scm(std::forward<T>(v)));
+
+template <typename T>
+auto to_cpp(SCM v)
+    -> SCM_DECLTYPE_RETURN(
+        convert<std::decay_t<T>>::to_cpp(v));
+
+} // namespace detail
+} // namespace scm
+
+#define SCM_DECLARE_NUMERIC_TYPE(cpp_name__, scm_name__)                \
+    namespace scm {                                                     \
+    namespace detail {                                                  \
+    template <>                                                         \
+    struct convert<cpp_name__> {                                        \
+        static cpp_name__ to_cpp(SCM v) { return scm_to_ ## scm_name__(v); } \
+        static SCM to_scm(cpp_name__ v) { return scm_from_ ## scm_name__(v); } \
+    };                                                                  \
+    }} /* namespace scm::detail */                                      \
+    /**/
+
+SCM_DECLARE_NUMERIC_TYPE(float,         double);
+SCM_DECLARE_NUMERIC_TYPE(double,        double);
+SCM_DECLARE_NUMERIC_TYPE(std::int8_t,   int8);
+SCM_DECLARE_NUMERIC_TYPE(std::int16_t,  int16);
+SCM_DECLARE_NUMERIC_TYPE(std::int32_t,  int32);
+SCM_DECLARE_NUMERIC_TYPE(std::int64_t,  int64);
+SCM_DECLARE_NUMERIC_TYPE(std::uint8_t,  uint8);
+SCM_DECLARE_NUMERIC_TYPE(std::uint16_t, uint16);
+SCM_DECLARE_NUMERIC_TYPE(std::uint32_t, uint32);
+SCM_DECLARE_NUMERIC_TYPE(std::uint64_t, uint64);