Internal improvements: new strong types StackIndex and KeeperIndex

1 files changed, 44 insertions, 0 deletions

diff --git a/src/unique.hpp b/src/unique.hpp
new file mode 100644
index 0000000..aeb7a67
--- /dev/null
+++ b/src/unique.hpp
@@ -0,0 +1,44 @@
+#pragma once
+
+// #################################################################################################
+
+// A unique type generator
+template <typename T, auto = [] {}, typename specialization = void>
+class Unique
+{
+    private:
+    T val;
+
+    public:
+    using type = T;
+    Unique() = default;
+    operator T() const { return val; }
+    explicit Unique(T b_)
+    : val{ b_ }
+    {
+    }
+    // pre-imcrement
+    auto& operator++()
+    {
+        ++val;
+        return *this;
+    }
+    // post-increment
+    auto operator++(int)
+    {
+        return Unique<T>{ std::exchange(val, val + 1) };
+    }
+};
+
+template <typename T, auto lambda>
+class Unique<T, lambda, std::enable_if_t<!std::is_scalar_v<T>>>
+: public T
+{
+    public:
+    using type = T;
+    using T::T;
+    explicit Unique(T const& b_)
+    : T{ b_ }
+    {
+    }
+};