evaulator: implement IR evaluation engine

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I980aaef64177b76620e3d1f9f39001046a6a6964

src/irc/evaluator.h

@@ -0,0 +1,35 @@
+#ifndef NIX_IRC_EVALUATOR_H
+#define NIX_IRC_EVALUATOR_H
+
+#include "types.h"
+#include <memory>
+#include <vector>
+
+namespace nix {
+class EvalState;
+class Value;
+class PosIdx;
+}
+
+namespace nix_irc {
+
+class IRValue;
+class IREnvironment;
+
+class Evaluator {
+public:
+    explicit Evaluator(nix::EvalState& state);
+    ~Evaluator();
+
+    void eval_to_nix(const std::shared_ptr<Node>& ir_node,
+                     nix::Value& result,
+                     IREnvironment* env = nullptr);
+
+private:
+    struct Impl;
+    std::unique_ptr<Impl> pImpl;
+};
+
+}
+
+#endif