Slightly improved version of the parser

cclox_src/parser/expr.cc

@@ -5,6 +5,26 @@
 #include <vector>
 #include <sstream>
 
+template <>
+Expr make_expr<Binary>(Binary value) {
+  return Expr(ExprType::BINARY, value);
+}
+
+template <>
+Expr make_expr<Grouping>(Grouping value) {
+  return Expr(ExprType::GROUPING, value);
+}
+
+template <>
+Expr make_expr<Literal>(Literal value) {
+  return Expr(ExprType::LITERAL, value);
+}
+
+template <>
+Expr make_expr<Unary>(Unary value) {
+  return Expr(ExprType::UNARY, value);
+}
+
 std::string AstPrinter::print(const Expr &expr) {
   switch (expr.type) {
     case ExprType::BINARY: {

cclox_src/parser/expr.hh

@@ -52,6 +52,9 @@ struct Expr {
   Expression value;
 };
 
+template <typename T>
+Expr make_expr(T value);
+
 class AstPrinter {
 public:
   std::string print(const Expr &expr);