Rename value.* and ast.* to expr.* and stmt.*, respectively
diff --git a/expr.h b/expr.h
new file mode 100644
index 0000000..606ef90
--- /dev/null
+++ b/expr.h
@@ -0,0 +1,71 @@
+// Copyright 2015 Google Inc. All rights reserved
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef EXPR_H_
+#define EXPR_H_
+
+#include <string>
+#include <vector>
+
+#include "string_piece.h"
+
+using namespace std;
+
+class Evaluator;
+struct Loc;
+
+class Evaluable {
+ public:
+ virtual void Eval(Evaluator* ev, string* s) const = 0;
+ string Eval(Evaluator*) const;
+
+ protected:
+ Evaluable();
+ virtual ~Evaluable();
+};
+
+class Value : public Evaluable {
+ public:
+ virtual ~Value();
+
+ virtual Value* Compact() { return this; }
+
+ string DebugString() const;
+
+ protected:
+ Value();
+ virtual string DebugString_() const = 0;
+};
+
+enum struct ParseExprOpt {
+ NORMAL = 0,
+ DEFINE,
+ COMMAND,
+ FUNC,
+};
+
+Value* ParseExprImpl(const Loc& loc, StringPiece s, const char* terms,
+ ParseExprOpt opt,
+ size_t* index_out, bool trim_right_space = false);
+Value* ParseExpr(const Loc& loc, StringPiece s,
+ ParseExprOpt opt = ParseExprOpt::NORMAL);
+
+string JoinValues(const vector<Value*>& vals, const char* sep);
+
+Value* NewExpr2(Value* v1, Value* v2);
+Value* NewExpr3(Value* v1, Value* v2, Value* v3);
+
+Value* NewLiteral(StringPiece s);
+
+#endif // EXPR_H_