Fix Object

cclox_src/object.cc

@@ -1,28 +1,41 @@
 #include "object.hh"
+#include <string>
 
-Object::Object(StringObjectType string_type, const std::string &value) : str{value} {
+std::ostream &operator<<(std::ostream &os, const ObjectType &type) {
-  switch (string_type) {
+  switch (type) {
-    case StringObjectType::IDENTIFIER:
-      type = ObjectType::IDENTIFIER;
-      break;
-    case StringObjectType::LITERAL:
-      type = ObjectType::STRING_LIT;
-      break;
-  }
-}
-
-std::ostream &operator<<(std::ostream &os, const Object &obj) {
-  switch (obj.type) {
     case ObjectType::NIL:
+      os << "ObjectType::NIL";
       break;
     case ObjectType::IDENTIFIER:
+      os << "ObjectType::IDENTIFIER";
+      break;
     case ObjectType::STRING_LIT:
-      os << obj.str;
+      os << "ObjectType::STRING_LIT";
       break;
     case ObjectType::NUMBER:
-      os << obj.number;
+      os << "ObjectType::NUMBER";
       break;
   }
 
   return os;
 }
+
+std::ostream &operator<<(std::ostream &os, const Object &obj) {
+  os << "Object(" << obj.type;
+
+  switch (obj.type) {
+    case ObjectType::NIL:
+      break;
+    case ObjectType::IDENTIFIER:
+    case ObjectType::STRING_LIT:
+      os << ", " << std::get<std::string>(obj.value);
+      break;
+    case ObjectType::NUMBER:
+      os << ", " << std::get<double>(obj.value);
+      break;
+  }
+
+  os << ')';
+
+  return os;
+}

cclox_src/object.hh

@@ -2,7 +2,7 @@
 
 #include <cstdint>
 #include <iostream>
-#include <string_view>
+#include <variant>
 
 enum class StringObjectType : uint8_t {
   IDENTIFIER,
@@ -17,15 +17,15 @@ enum class ObjectType : uint8_t {
 };
 
 struct Object {
-  Object() : type{ObjectType::NIL} {};
+  Object() : type{ObjectType::NIL}, value{std::monostate{}} {};
-  Object(double number) : type{ObjectType::NUMBER}, number{number} {};
+  Object(double number) : type{ObjectType::NUMBER}, value{number} {};
-  Object(StringObjectType string_type, const std::string &value);
+  Object(StringObjectType string_type, std::string value)
+    : type{string_type == StringObjectType::IDENTIFIER ? ObjectType::IDENTIFIER : ObjectType::STRING_LIT},
+      value{std::move(value)} {};
 
   ObjectType type;
-  union {
+  std::variant<std::monostate, std::string, double> value;
-    std::string_view str;
-    double number;
-  };
 };
 
+std::ostream &operator<<(std::ostream &os, const ObjectType &type);
 std::ostream &operator<<(std::ostream &os, const Object &obj);

cclox_src/scanner.cc

@@ -116,6 +116,8 @@ void Scanner::string() {
   advance();
 
   // Trim the surrounding quotes.
-  std::string value = code.substr(start + 1, current - 1);
+  size_t no_quote_start = start + 1;
+  size_t no_quote_end = current - 1;
+  std::string value = code.substr(no_quote_start, no_quote_end - no_quote_start);
   add_token(TokenType::STRING, Object(StringObjectType::LITERAL, value));
 }

cclox_src/token.hh

@@ -3,7 +3,7 @@
 #include "object.hh"
 #include <cstdint>
 #include <string>
-#include <string_view>
+#include <utility>
 
 enum class TokenType : uint8_t {
   // Single-character tokens.
@@ -27,12 +27,12 @@ enum class TokenType : uint8_t {
 };
 
 struct Token {
-  Token(TokenType type, const std::string &lexeme, Object literal, int line)
+  Token(TokenType type, std::string lexeme, Object literal, int line)
-    : type{type}, lexeme{lexeme}, literal{literal}, line{line}
+    : type{type}, lexeme{std::move(lexeme)}, literal{literal}, line{line}
   {};
 
   TokenType type;
-  std::string_view lexeme;
+  std::string lexeme;
   Object literal;
   int line;
 };