riyyi
/
manafiles
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
Browse Source

Util: Implement copy-and-swap idiom and the Rule of Five in Value

master
Riyyi 2 years ago
parent
a1bb1b93c9
commit
3e69abdfa0
5 changed files with 131 additions and 92 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 1
      src/util/json/array.h
  2. 1
      src/util/json/object.h
  3. 38
      src/util/json/tojson.h
  4. 157
      src/util/json/value.cpp
  5. 22
      src/util/json/value.h

1
src/util/json/array.h
Unescape View File

@ -30,6 +30,7 @@ public:
{
}
void clear() { m_elements.clear(); }
void emplace_back(Value element);
void reserve(size_t size) { m_elements.reserve(size); }

1
src/util/json/object.h
Unescape View File

@ -27,6 +27,7 @@ public:
{
}
void clear() { m_members.clear(); }
void emplace(const std::string& name, Value value);
Value& operator[](const std::string& name);

38
src/util/json/tojson.h
Unescape View File

@ -26,7 +26,7 @@ struct jsonConstructor {
template<typename Json>
static void construct(Json& json, bool boolean)
{
json.clear();
json.destroy();
json.m_type = Json::Type::Bool;
json.m_value.boolean = boolean;
}
@ -34,7 +34,7 @@ struct jsonConstructor {
template<typename Json>
static void construct(Json& json, int number)
{
json.clear();
json.destroy();
json.m_type = Json::Type::Number;
json.m_value.number = (double)number;
}
@ -42,7 +42,7 @@ struct jsonConstructor {
template<typename Json>
static void construct(Json& json, double number)
{
json.clear();
json.destroy();
json.m_type = Json::Type::Number;
json.m_value.number = number;
}
@ -50,7 +50,7 @@ struct jsonConstructor {
template<typename Json>
static void construct(Json& json, const char* string)
{
json.clear();
json.destroy();
json.m_type = Json::Type::String;
json.m_value.string = new std::string(string);
}
@ -58,7 +58,7 @@ struct jsonConstructor {
template<typename Json>
static void construct(Json& json, const std::string& string)
{
json.clear();
json.destroy();
json.m_type = Json::Type::String;
json.m_value.string = new std::string(string);
}
@ -66,7 +66,7 @@ struct jsonConstructor {
template<typename Json>
static void construct(Json& json, const Array& array)
{
json.clear();
json.destroy();
json.m_type = Json::Type::Array;
json.m_value.array = new Array(array);
}
@ -74,7 +74,7 @@ struct jsonConstructor {
template<typename Json, typename T>
static void construct(Json& json, const std::vector<T>& array)
{
json.clear();
json.destroy();
json.m_type = Json::Type::Array;
json.m_value.array = new Array;
json.m_value.array->reserve(array.size());
@ -86,7 +86,7 @@ struct jsonConstructor {
template<typename Json>
static void construct(Json& json, const Object& object)
{
json.clear();
json.destroy();
json.m_type = Json::Type::Object;
json.m_value.object = new Object(object);
}
@ -94,7 +94,7 @@ struct jsonConstructor {
template<typename Json, typename T>
static void construct(Json& json, const std::map<std::string, T>& object)
{
json.clear();
json.destroy();
json.m_type = Json::Type::Object;
json.m_value.object = new Object;
for (const auto& [name, value] : object) {
@ -105,7 +105,7 @@ struct jsonConstructor {
template<typename Json, typename T>
static void construct(Json& json, const std::unordered_map<std::string, T>& object)
{
json.clear();
json.destroy();
json.m_type = Json::Type::Object;
json.m_value.object = new Object;
for (const auto& [name, value] : object) {
@ -143,14 +143,14 @@ constexpr const auto& toJson = Detail::staticConst<Detail::toJsonFunction>; // N
// Customization Points
// https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4381.html
// Json::fromJson is a function object, the type of which is
// Json::Detail::fromJsonFunction. In the Json::Detail namespace are the
// fromJson free functions. The function call operator of fromJsonFunction makes
// an unqualified call to fromJson which, since it shares the Detail namespace
// with the fromJson free functions, will consider those in addition to any
// overloads that are found by argument-dependent lookup.
// Json::toJson is a function object, the type of which is
// Json::Detail::toJsonFunction. In the Json::Detail namespace are the toJson
// free functions. The function call operator of toJsonFunction makes an
// unqualified call to toJson which, since it shares the Detail namespace with
// the toJson free functions, will consider those in addition to any overloads
// that are found by argument-dependent lookup.
// Variable templates are linked externally, therefor every translation unit
// will see the same address for Detail::staticConst<Detail::fromJsonFunction>.
// Since Json::fromJson is a reference to the variable template, it too will
// have the same address in all translation units.
// will see the same address for Detail::staticConst<Detail::toJsonFunction>.
// Since Json::toJson is a reference to the variable template, it too will have
// the same address in all translation units.

157
src/util/json/value.cpp
Unescape View File

@ -9,7 +9,7 @@
#include <cstdint> // uint32_t
#include <iostream> // istream, ostream
#include <string>
#include <utility> // move
#include <utility> // move, swap
#include "util/json/array.h"
#include "util/json/job.h"
@ -27,7 +27,26 @@ Value::Value(std::nullptr_t)
Value::Value(Type type)
: m_type(type)
{
create();
switch (m_type) {
case Type::Bool:
m_value.boolean = false;
break;
case Type::Number:
m_value.number = 0.0;
break;
case Type::String:
m_value.string = new std::string;
break;
case Type::Array:
m_value.array = new Array;
break;
case Type::Object:
m_value.object = new Object;
break;
case Type::Null:
default:
break;
}
}
Value::Value(const std::initializer_list<Value>& values)
@ -55,29 +74,87 @@ Value::Value(const std::initializer_list<Value>& values)
// Copy constructor
Value::Value(const Value& other)
: m_type(other.m_type)
{
copyFrom(other);
switch (m_type) {
case Type::Bool:
m_value.boolean = other.m_value.boolean;
break;
case Type::Number:
m_value.number = other.m_value.number;
break;
case Type::String:
m_value.string = new std::string(*other.m_value.string);
break;
case Type::Array:
m_value.array = new Array(*other.m_value.array);
break;
case Type::Object:
m_value.object = new Object(*other.m_value.object);
break;
case Type::Null:
default:
break;
}
}
// Assignment operator
Value& Value::operator=(const Value& other)
// Move constructor
Value::Value(Value&& other) noexcept
: Value(Type::Null) // Initialize via default construction
{
if (this != &other) {
clear();
copyFrom(other);
// Allow std::swap as a fallback on ADL failure
using std::swap;
// Unqualified call to swap, allow ADL to operate and find best match
swap(*this, other);
}
// Copy assignment
// Move assignment
Value& Value::operator=(Value other)
{
// Allow std::swap as a fallback on ADL failure
using std::swap;
// Unqualified call to swap, allow ADL to operate and find best match
swap(*this, other);
return *this;
}
void swap(Value& left, Value& right) noexcept
{
std::swap(left.m_type, right.m_type);
std::swap(left.m_value, right.m_value);
}
// ------------------------------------------
Value Value::parse(const std::string& input)
void Value::clear()
{
Job job(input);
Value value = job.fire();
switch (m_type) {
case Type::Bool:
m_value.boolean = false;
break;
case Type::Number:
m_value.number = 0.0;
break;
case Type::String:
m_value.string->clear();
break;
case Type::Array:
m_value.array->clear();
break;
case Type::Object:
m_value.object->clear();
break;
case Type::Null:
default:
break;
}
}
return value;
Value Value::parse(const std::string& input)
{
return Job(input).fire();
}
std::string Value::dump(const uint32_t indent, const char indentCharacter) const
@ -190,45 +267,21 @@ size_t Value::size() const
switch (m_type) {
case Type::Null:
return 0;
case Type::Bool:
case Type::Number:
case Type::String:
return 1;
case Type::Array:
return m_value.array->size();
case Type::Object:
return m_value.object->size();
default:
return 1;
}
}
// ------------------------------------------
void Value::create()
{
switch (m_type) {
case Type::Bool:
m_value.boolean = false;
break;
case Type::Number:
m_value.number = 0.0;
break;
case Type::String:
m_value.string = new std::string;
break;
case Type::Array:
m_value.array = new Array;
break;
case Type::Object:
m_value.object = new Object;
break;
default:
break;
return 1;
}
}
void Value::clear()
// ------------------------------------------
void Value::destroy()
{
switch (m_type) {
case Type::String:
@ -240,31 +293,9 @@ void Value::clear()
case Type::Object:
delete m_value.object;
break;
default:
break;
}
}
void Value::copyFrom(const Value& other)
{
m_type = other.m_type;
switch (m_type) {
case Type::Null:
case Type::Bool:
m_value.boolean = other.m_value.boolean;
break;
case Type::Number:
m_value.number = other.m_value.number;
break;
case Type::String:
m_value.string = new std::string(*other.m_value.string);
break;
case Type::Array:
m_value.array = new Array(*other.m_value.array);
break;
case Type::Object:
m_value.object = new Object(*other.m_value.object);
break;
default:
break;
}

22
src/util/json/value.h
Unescape View File

@ -38,6 +38,8 @@ public:
Object, // {}
};
// --------------------------------------
// Constructors
Value(std::nullptr_t = nullptr);
Value(Type type);
@ -48,20 +50,26 @@ public:
toJson(*this, std::forward<T>(value));
}
// Destructor
virtual ~Value() { clear(); }
// Rule of Five:
// Copy constructor
Value(const Value& other);
// Move constructor
Value(Value&& other) noexcept;
// Copy assignment
// Move assignment
Value& operator=(Value other);
// Destructor
virtual ~Value() { destroy(); }
// Assignment operator
Value& operator=(const Value& other);
friend void swap(Value& left, Value& right) noexcept;
// --------------------------------------
static Value parse(const std::string& input);
std::string dump(const uint32_t indent = 0, const char indentCharacter = ' ') const;
void clear();
void emplace_back(Value value);
void emplace(const std::string& key, Value value);
@ -109,9 +117,7 @@ public:
const Object& asObject() const { return *m_value.object; }
private:
void create();
void clear();
void copyFrom(const Value& other);
void destroy();
Type m_type { Type::Null };

Write Preview
Loading…
Cancel
Save