[C++] The first commit for C++ version
16 tests out of 169 are passing.
diff --git a/var.h b/var.h
new file mode 100644
index 0000000..bb7ab31
--- /dev/null
+++ b/var.h
@@ -0,0 +1,101 @@
+#ifndef VAR_H_
+#define VAR_H_
+
+#include <memory>
+#include <string>
+#include <unordered_map>
+
+#include "string_piece.h"
+#include "value.h"
+
+using namespace std;
+
+class Evaluator;
+class Value;
+
+class Var : public Evaluable {
+ public:
+ virtual ~Var();
+
+ virtual const char* Flavor() const = 0;
+ virtual const char* Origin() const = 0;
+ virtual bool IsDefined() const { return true; }
+
+ virtual string DebugString() const = 0;
+
+ protected:
+ Var();
+};
+
+class SimpleVar : public Var {
+ public:
+ SimpleVar(shared_ptr<string> v, const char* origin);
+
+ virtual const char* Flavor() const {
+ return "simple";
+ }
+ virtual const char* Origin() const {
+ return origin_;
+ }
+
+ virtual shared_ptr<string> Eval(Evaluator*) const override {
+ return v_;
+ }
+ virtual void Eval(Evaluator* ev, string* s) const override;
+
+ string DebugString() const override;
+
+ private:
+ shared_ptr<string> v_;
+ const char* origin_;
+};
+
+class RecursiveVar : public Var {
+ public:
+ RecursiveVar(Value* v, const char* origin);
+
+ virtual const char* Flavor() const {
+ return "recursive";
+ }
+ virtual const char* Origin() const {
+ return origin_;
+ }
+
+ virtual void Eval(Evaluator* ev, string* s) const override;
+
+ string DebugString() const override;
+
+ private:
+ Value* v_;
+ const char* origin_;
+};
+
+class UndefinedVar : public Var {
+ public:
+ UndefinedVar();
+
+ virtual const char* Flavor() const {
+ return "undefined";
+ }
+ virtual const char* Origin() const {
+ return "undefined";
+ }
+ virtual bool IsDefined() const { return false; }
+
+ virtual void Eval(Evaluator* ev, string* s) const override;
+
+ string DebugString() const override;
+};
+
+extern UndefinedVar* kUndefined;
+
+class Vars : public unordered_map<StringPiece, Var*> {
+ public:
+ ~Vars();
+
+ Var* Lookup(StringPiece name) const;
+
+ void Assign(StringPiece name, Var* v);
+};
+
+#endif // VAR_H_