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#ifndef SRC_NAPI_H_
#define SRC_NAPI_H_
#ifndef NAPI_HAS_THREADS
#if !defined(__wasm__) || (defined(__EMSCRIPTEN_PTHREADS__) || \
(defined(__wasi__) && defined(_REENTRANT)))
#define NAPI_HAS_THREADS 1
#else
#define NAPI_HAS_THREADS 0
#endif
#endif
#include <node_api.h>
#include <functional>
#include <initializer_list>
#include <memory>
#if NAPI_HAS_THREADS
#include <mutex>
#endif // NAPI_HAS_THREADS
#include <chrono>
#include <string>
#include <string_view>
#include <type_traits>
#include <utility>
#include <vector>
// VS2015 RTM has bugs with constexpr, so require min of VS2015 Update 3 (known
// good version)
#if !defined(_MSC_VER) || _MSC_FULL_VER >= 190024210
#define NAPI_HAS_CONSTEXPR 1
#endif
// VS2013 does not support char16_t literal strings, so we'll work around it
// using wchar_t strings and casting them. This is safe as long as the character
// sizes are the same.
#if defined(_MSC_VER) && _MSC_VER <= 1800
static_assert(sizeof(char16_t) == sizeof(wchar_t),
"Size mismatch between char16_t and wchar_t");
#define NAPI_WIDE_TEXT(x) reinterpret_cast<char16_t*>(L##x)
#else
#define NAPI_WIDE_TEXT(x) u##x
#endif
// Backwards-compatibility to handle the rename of this macro definition, in
// case they are used within userland code.
#ifdef NAPI_CPP_EXCEPTIONS
#define NODE_ADDON_API_CPP_EXCEPTIONS
#endif
#if defined(NODE_ADDON_API_CPP_EXCEPTIONS) && !defined(NAPI_CPP_EXCEPTIONS)
#define NAPI_CPP_EXCEPTIONS
#endif
#ifdef NAPI_DISABLE_CPP_EXCEPTIONS
#define NODE_ADDON_API_DISABLE_CPP_EXCEPTIONS
#endif
#if defined(NODE_ADDON_API_DISABLE_CPP_EXCEPTIONS) && \
!defined(NAPI_DISABLE_CPP_EXCEPTIONS)
#define NAPI_DISABLE_CPP_EXCEPTIONS
#endif
// If C++ exceptions are not explicitly enabled or disabled, enable them
// if exceptions were enabled in the compiler settings.
#if !defined(NODE_ADDON_API_CPP_EXCEPTIONS) && \
!defined(NODE_ADDON_API_DISABLE_CPP_EXCEPTIONS)
#if defined(_CPPUNWIND) || defined(__EXCEPTIONS)
#define NODE_ADDON_API_CPP_EXCEPTIONS
#else
#error Exception support not detected. \
Define either NODE_ADDON_API_CPP_EXCEPTIONS or NODE_ADDON_API_DISABLE_CPP_EXCEPTIONS.
#endif
#endif
// If C++ NODE_ADDON_API_CPP_EXCEPTIONS are enabled, NODE_ADDON_API_ENABLE_MAYBE
// should not be set
#if defined(NODE_ADDON_API_CPP_EXCEPTIONS) && \
defined(NODE_ADDON_API_ENABLE_MAYBE)
#error NODE_ADDON_API_ENABLE_MAYBE should not be set when \
NODE_ADDON_API_CPP_EXCEPTIONS is defined.
#endif
#ifdef _NOEXCEPT
#define NAPI_NOEXCEPT _NOEXCEPT
#else
#define NAPI_NOEXCEPT noexcept
#endif
#ifdef NODE_ADDON_API_CPP_EXCEPTIONS
// When C++ exceptions are enabled, Errors are thrown directly. There is no need
// to return anything after the throw statements. The variadic parameter is an
// optional return value that is ignored.
// We need _VOID versions of the macros to avoid warnings resulting from
// leaving the NAPI_THROW_* `...` argument empty.
#define NAPI_THROW(e, ...) throw e
#define NAPI_THROW_VOID(e) throw e
#define NAPI_THROW_IF_FAILED(env, status, ...) \
if ((status) != napi_ok) throw Napi::Error::New(env);
#define NAPI_THROW_IF_FAILED_VOID(env, status) \
if ((status) != napi_ok) throw Napi::Error::New(env);
#else // NODE_ADDON_API_CPP_EXCEPTIONS
// When C++ exceptions are disabled, Errors are thrown as JavaScript exceptions,
// which are pending until the callback returns to JS. The variadic parameter
// is an optional return value; usually it is an empty result.
// We need _VOID versions of the macros to avoid warnings resulting from
// leaving the NAPI_THROW_* `...` argument empty.
#define NAPI_THROW(e, ...) \
do { \
(e).ThrowAsJavaScriptException(); \
return __VA_ARGS__; \
} while (0)
#define NAPI_THROW_VOID(e) \
do { \
(e).ThrowAsJavaScriptException(); \
return; \
} while (0)
#define NAPI_THROW_IF_FAILED(env, status, ...) \
if ((status) != napi_ok) { \
Napi::Error::New(env).ThrowAsJavaScriptException(); \
return __VA_ARGS__; \
}
#define NAPI_THROW_IF_FAILED_VOID(env, status) \
if ((status) != napi_ok) { \
Napi::Error::New(env).ThrowAsJavaScriptException(); \
return; \
}
#endif // NODE_ADDON_API_CPP_EXCEPTIONS
#ifdef NODE_ADDON_API_ENABLE_MAYBE
#define NAPI_MAYBE_THROW_IF_FAILED(env, status, type) \
NAPI_THROW_IF_FAILED(env, status, Napi::Nothing<type>())
#define NAPI_RETURN_OR_THROW_IF_FAILED(env, status, result, type) \
NAPI_MAYBE_THROW_IF_FAILED(env, status, type); \
return Napi::Just<type>(result);
#else
#define NAPI_MAYBE_THROW_IF_FAILED(env, status, type) \
NAPI_THROW_IF_FAILED(env, status, type())
#define NAPI_RETURN_OR_THROW_IF_FAILED(env, status, result, type) \
NAPI_MAYBE_THROW_IF_FAILED(env, status, type); \
return result;
#endif
#define NAPI_DISALLOW_ASSIGN(CLASS) void operator=(const CLASS&) = delete;
#define NAPI_DISALLOW_COPY(CLASS) CLASS(const CLASS&) = delete;
#define NAPI_DISALLOW_ASSIGN_COPY(CLASS) \
NAPI_DISALLOW_ASSIGN(CLASS) \
NAPI_DISALLOW_COPY(CLASS)
#define NAPI_CHECK(condition, location, message) \
do { \
if (!(condition)) { \
Napi::Error::Fatal((location), (message)); \
} \
} while (0)
// Internal check helper. Be careful that the formatted message length should be
// max 255 size and null terminated.
#define NAPI_INTERNAL_CHECK(expr, location, ...) \
do { \
if (!(expr)) { \
std::string msg = Napi::details::StringFormat(__VA_ARGS__); \
Napi::Error::Fatal(location, msg.c_str()); \
} \
} while (0)
#define NAPI_INTERNAL_CHECK_EQ(actual, expected, value_format, location) \
do { \
auto actual_value = (actual); \
NAPI_INTERNAL_CHECK(actual_value == (expected), \
location, \
"Expected " #actual " to be equal to " #expected \
", but got " value_format ".", \
actual_value); \
} while (0)
#define NAPI_FATAL_IF_FAILED(status, location, message) \
NAPI_CHECK((status) == napi_ok, location, message)
////////////////////////////////////////////////////////////////////////////////
/// Node-API C++ Wrapper Classes
///
/// These classes wrap the "Node-API" ABI-stable C APIs for Node.js, providing a
/// C++ object model and C++ exception-handling semantics with low overhead.
/// The wrappers are all header-only so that they do not affect the ABI.
////////////////////////////////////////////////////////////////////////////////
namespace Napi {
#ifdef NAPI_CPP_CUSTOM_NAMESPACE
// NAPI_CPP_CUSTOM_NAMESPACE can be #define'd per-addon to avoid symbol
// conflicts between different instances of node-addon-api
// First dummy definition of the namespace to make sure that Napi::(name) still
// refers to the right things inside this file.
namespace NAPI_CPP_CUSTOM_NAMESPACE {}
using namespace NAPI_CPP_CUSTOM_NAMESPACE;
namespace NAPI_CPP_CUSTOM_NAMESPACE {
#endif
// Forward declarations
class Env;
class Value;
class Boolean;
class Number;
#if NAPI_VERSION > 5
class BigInt;
#endif // NAPI_VERSION > 5
#if (NAPI_VERSION > 4)
class Date;
#endif
class String;
class Object;
class Array;
class ArrayBuffer;
class Function;
class Error;
class PropertyDescriptor;
class CallbackInfo;
class TypedArray;
template <typename T>
class TypedArrayOf;
using Int8Array =
TypedArrayOf<int8_t>; ///< Typed-array of signed 8-bit integers
using Uint8Array =
TypedArrayOf<uint8_t>; ///< Typed-array of unsigned 8-bit integers
using Int16Array =
TypedArrayOf<int16_t>; ///< Typed-array of signed 16-bit integers
using Uint16Array =
TypedArrayOf<uint16_t>; ///< Typed-array of unsigned 16-bit integers
using Int32Array =
TypedArrayOf<int32_t>; ///< Typed-array of signed 32-bit integers
using Uint32Array =
TypedArrayOf<uint32_t>; ///< Typed-array of unsigned 32-bit integers
using Float32Array =
TypedArrayOf<float>; ///< Typed-array of 32-bit floating-point values
using Float64Array =
TypedArrayOf<double>; ///< Typed-array of 64-bit floating-point values
#if NAPI_VERSION > 5
using BigInt64Array =
TypedArrayOf<int64_t>; ///< Typed array of signed 64-bit integers
using BigUint64Array =
TypedArrayOf<uint64_t>; ///< Typed array of unsigned 64-bit integers
#endif // NAPI_VERSION > 5
/// Defines the signature of a Node-API C++ module's registration callback
/// (init) function.
using ModuleRegisterCallback = Object (*)(Env env, Object exports);
class MemoryManagement;
/// A simple Maybe type, representing an object which may or may not have a
/// value.
///
/// If an API method returns a Maybe<>, the API method can potentially fail
/// either because an exception is thrown, or because an exception is pending,
/// e.g. because a previous API call threw an exception that hasn't been
/// caught yet. In that case, a "Nothing" value is returned.
template <class T>
class Maybe {
public:
bool IsNothing() const;
bool IsJust() const;
/// Short-hand for Unwrap(), which doesn't return a value. Could be used
/// where the actual value of the Maybe is not needed like Object::Set.
/// If this Maybe is nothing (empty), node-addon-api will crash the
/// process.
void Check() const;
/// Return the value of type T contained in the Maybe. If this Maybe is
/// nothing (empty), node-addon-api will crash the process.
T Unwrap() const;
/// Return the value of type T contained in the Maybe, or using a default
/// value if this Maybe is nothing (empty).
T UnwrapOr(const T& default_value) const;
/// Converts this Maybe to a value of type T in the out. If this Maybe is
/// nothing (empty), `false` is returned and `out` is left untouched.
bool UnwrapTo(T* out) const;
bool operator==(const Maybe& other) const;
bool operator!=(const Maybe& other) const;
private:
Maybe();
explicit Maybe(const T& t);
bool _has_value;
T _value;
template <class U>
friend Maybe<U> Nothing();
template <class U>
friend Maybe<U> Just(const U& u);
};
template <class T>
inline Maybe<T> Nothing();
template <class T>
inline Maybe<T> Just(const T& t);
#if defined(NODE_ADDON_API_ENABLE_MAYBE)
template <typename T>
using MaybeOrValue = Maybe<T>;
#else
template <typename T>
using MaybeOrValue = T;
#endif
#ifdef NODE_API_EXPERIMENTAL_HAS_POST_FINALIZER
using node_addon_api_basic_env = node_api_nogc_env;
using node_addon_api_basic_finalize = node_api_nogc_finalize;
#else
using node_addon_api_basic_env = napi_env;
using node_addon_api_basic_finalize = napi_finalize;
#endif
/// Environment for Node-API values and operations.
///
/// All Node-API values and operations must be associated with an environment.
/// An environment instance is always provided to callback functions; that
/// environment must then be used for any creation of Node-API values or other
/// Node-API operations within the callback. (Many methods infer the
/// environment from the `this` instance that the method is called on.)
///
/// Multiple environments may co-exist in a single process or a thread.
///
/// In the V8 JavaScript engine, a Node-API environment approximately
/// corresponds to an Isolate.
class BasicEnv {
private:
node_addon_api_basic_env _env;
#if NAPI_VERSION > 5
template <typename T>
static void DefaultFini(Env, T* data);
template <typename DataType, typename HintType>
static void DefaultFiniWithHint(Env, DataType* data, HintType* hint);
#endif // NAPI_VERSION > 5
public:
BasicEnv(node_addon_api_basic_env env);
operator node_addon_api_basic_env() const;
// Without these operator overloads, the error:
//
// Use of overloaded operator '==' is ambiguous (with operand types
// 'Napi::Env' and 'Napi::Env')
//
// ... occurs when comparing foo.Env() == bar.Env() or foo.Env() == nullptr
bool operator==(const BasicEnv& other) const {
return _env == other._env;
}
bool operator==(std::nullptr_t /*other*/) const {
return _env == nullptr;
}
#if NAPI_VERSION > 2
template <typename Hook, typename Arg = void>
class CleanupHook;
template <typename Hook>
CleanupHook<Hook> AddCleanupHook(Hook hook);
template <typename Hook, typename Arg>
CleanupHook<Hook, Arg> AddCleanupHook(Hook hook, Arg* arg);
#endif // NAPI_VERSION > 2
#if NAPI_VERSION > 5
template <typename T>
T* GetInstanceData() const;
template <typename T>
using Finalizer = void (*)(Env, T*);
template <typename T, Finalizer<T> fini = BasicEnv::DefaultFini<T>>
void SetInstanceData(T* data) const;
template <typename DataType, typename HintType>
using FinalizerWithHint = void (*)(Env, DataType*, HintType*);
template <typename DataType,
typename HintType,
FinalizerWithHint<DataType, HintType> fini =
BasicEnv::DefaultFiniWithHint<DataType, HintType>>
void SetInstanceData(DataType* data, HintType* hint) const;
#endif // NAPI_VERSION > 5
#if NAPI_VERSION > 2
template <typename Hook, typename Arg>
class CleanupHook {
public:
CleanupHook();
CleanupHook(BasicEnv env, Hook hook, Arg* arg);
CleanupHook(BasicEnv env, Hook hook);
bool Remove(BasicEnv env);
bool IsEmpty() const;
private:
static inline void Wrapper(void* data) NAPI_NOEXCEPT;
static inline void WrapperWithArg(void* data) NAPI_NOEXCEPT;
void (*wrapper)(void* arg);
struct CleanupData {
Hook hook;
Arg* arg;
} * data;
};
#endif // NAPI_VERSION > 2
#if NAPI_VERSION > 8
const char* GetModuleFileName() const;
#endif // NAPI_VERSION > 8
#ifdef NODE_API_EXPERIMENTAL_HAS_POST_FINALIZER
// FinalizerType must implement `void operator()(Env env)`.
template <typename FinalizerType>
inline void PostFinalizer(FinalizerType finalizeCallback) const;
// FinalizerType must implement `void operator()(Env env, T* data)`.
template <typename FinalizerType, typename T>
inline void PostFinalizer(FinalizerType finalizeCallback, T* data) const;
// FinalizerType must implement `void operator()(Env env, T* data,
// Hint* hint)`.
template <typename FinalizerType, typename T, typename Hint>
inline void PostFinalizer(FinalizerType finalizeCallback,
T* data,
Hint* finalizeHint) const;
#endif // NODE_API_EXPERIMENTAL_HAS_POST_FINALIZER
friend class Env;
};
class Env : public BasicEnv {
public:
Env(napi_env env);
operator napi_env() const;
Object Global() const;
Value Undefined() const;
Value Null() const;
bool IsExceptionPending() const;
Error GetAndClearPendingException() const;
MaybeOrValue<Value> RunScript(const char* utf8script) const;
MaybeOrValue<Value> RunScript(const std::string& utf8script) const;
MaybeOrValue<Value> RunScript(String script) const;
};
/// A JavaScript value of unknown type.
///
/// For type-specific operations, convert to one of the Value subclasses using a
/// `To*` or `As()` method. The `To*` methods do type coercion; the `As()`
/// method does not.
///
/// Napi::Value value = ...
/// if (!value.IsString()) throw Napi::TypeError::New(env, "Invalid
/// arg..."); Napi::String str = value.As<Napi::String>(); // Cast to a
/// string value
///
/// Napi::Value anotherValue = ...
/// bool isTruthy = anotherValue.ToBoolean(); // Coerce to a boolean value
class Value {
public:
Value(); ///< Creates a new _empty_ Value instance.
Value(napi_env env,
napi_value value); ///< Wraps a Node-API value primitive.
/// Creates a JS value from a C++ primitive.
///
/// `value` may be any of:
/// - bool
/// - Any integer type
/// - Any floating point type
/// - const char* (encoded using UTF-8, null-terminated)
/// - const char16_t* (encoded using UTF-16-LE, null-terminated)
/// - std::string (encoded using UTF-8)
/// - std::u16string
/// - napi::Value
/// - napi_value
template <typename T>
static Value From(napi_env env, const T& value);
static void CheckCast(napi_env env, napi_value value);
/// Converts to a Node-API value primitive.
///
/// If the instance is _empty_, this returns `nullptr`.
operator napi_value() const;
/// Tests if this value strictly equals another value.
bool operator==(const Value& other) const;
/// Tests if this value does not strictly equal another value.
bool operator!=(const Value& other) const;
/// Tests if this value strictly equals another value.
bool StrictEquals(const Value& other) const;
/// Gets the environment the value is associated with.
Napi::Env Env() const;
/// Checks if the value is empty (uninitialized).
///
/// An empty value is invalid, and most attempts to perform an operation on an
/// empty value will result in an exception. Note an empty value is distinct
/// from JavaScript `null` or `undefined`, which are valid values.
///
/// When C++ exceptions are disabled at compile time, a method with a `Value`
/// return type may return an empty value to indicate a pending exception. So
/// when not using C++ exceptions, callers should check whether the value is
/// empty before attempting to use it.
bool IsEmpty() const;
napi_valuetype Type() const; ///< Gets the type of the value.
bool IsUndefined()
const; ///< Tests if a value is an undefined JavaScript value.
bool IsNull() const; ///< Tests if a value is a null JavaScript value.
bool IsBoolean() const; ///< Tests if a value is a JavaScript boolean.
bool IsNumber() const; ///< Tests if a value is a JavaScript number.
#if NAPI_VERSION > 5
bool IsBigInt() const; ///< Tests if a value is a JavaScript bigint.
#endif // NAPI_VERSION > 5
#if (NAPI_VERSION > 4)
bool IsDate() const; ///< Tests if a value is a JavaScript date.
#endif
bool IsString() const; ///< Tests if a value is a JavaScript string.
bool IsSymbol() const; ///< Tests if a value is a JavaScript symbol.
bool IsArray() const; ///< Tests if a value is a JavaScript array.
bool IsArrayBuffer()
const; ///< Tests if a value is a JavaScript array buffer.
bool IsTypedArray() const; ///< Tests if a value is a JavaScript typed array.
bool IsObject() const; ///< Tests if a value is a JavaScript object.
bool IsFunction() const; ///< Tests if a value is a JavaScript function.
bool IsPromise() const; ///< Tests if a value is a JavaScript promise.
bool IsDataView() const; ///< Tests if a value is a JavaScript data view.
bool IsBuffer() const; ///< Tests if a value is a Node buffer.
bool IsExternal() const; ///< Tests if a value is a pointer to external data.
#ifdef NODE_API_EXPERIMENTAL_HAS_SHAREDARRAYBUFFER
bool IsSharedArrayBuffer() const;
#endif
/// Casts to another type of `Napi::Value`, when the actual type is known or
/// assumed.
///
/// This conversion does NOT coerce the type. Calling any methods
/// inappropriate for the actual value type will throw `Napi::Error`.
///
/// If `NODE_ADDON_API_ENABLE_TYPE_CHECK_ON_AS` is defined, this method
/// asserts that the actual type is the expected type.
template <typename T>
T As() const;
// Unsafe Value::As(), should be avoided.
template <typename T>
T UnsafeAs() const;
MaybeOrValue<Boolean> ToBoolean()
const; ///< Coerces a value to a JavaScript boolean.
MaybeOrValue<Number> ToNumber()
const; ///< Coerces a value to a JavaScript number.
MaybeOrValue<String> ToString()
const; ///< Coerces a value to a JavaScript string.
MaybeOrValue<Object> ToObject()
const; ///< Coerces a value to a JavaScript object.
protected:
/// !cond INTERNAL
napi_env _env;
napi_value _value;
/// !endcond
};
/// A JavaScript boolean value.
class Boolean : public Value {
public:
static Boolean New(napi_env env, ///< Node-API environment
bool value ///< Boolean value
);
static void CheckCast(napi_env env, napi_value value);
Boolean(); ///< Creates a new _empty_ Boolean instance.
Boolean(napi_env env,
napi_value value); ///< Wraps a Node-API value primitive.
operator bool() const; ///< Converts a Boolean value to a boolean primitive.
bool Value() const; ///< Converts a Boolean value to a boolean primitive.
};
/// A JavaScript number value.
class Number : public Value {
public:
static Number New(napi_env env, ///< Node-API environment
double value ///< Number value
);
static void CheckCast(napi_env env, napi_value value);
Number(); ///< Creates a new _empty_ Number instance.
Number(napi_env env,
napi_value value); ///< Wraps a Node-API value primitive.
operator int32_t()
const; ///< Converts a Number value to a 32-bit signed integer value.
operator uint32_t()
const; ///< Converts a Number value to a 32-bit unsigned integer value.
operator int64_t()
const; ///< Converts a Number value to a 64-bit signed integer value.
operator float()
const; ///< Converts a Number value to a 32-bit floating-point value.
operator double()
const; ///< Converts a Number value to a 64-bit floating-point value.
int32_t Int32Value()
const; ///< Converts a Number value to a 32-bit signed integer value.
uint32_t Uint32Value()
const; ///< Converts a Number value to a 32-bit unsigned integer value.
int64_t Int64Value()
const; ///< Converts a Number value to a 64-bit signed integer value.
float FloatValue()
const; ///< Converts a Number value to a 32-bit floating-point value.
double DoubleValue()
const; ///< Converts a Number value to a 64-bit floating-point value.
};
#if NAPI_VERSION > 5
/// A JavaScript bigint value.
class BigInt : public Value {
public:
static BigInt New(napi_env env, ///< Node-API environment
int64_t value ///< Number value
);
static BigInt New(napi_env env, ///< Node-API environment
uint64_t value ///< Number value
);
/// Creates a new BigInt object using a specified sign bit and a
/// specified list of digits/words.
/// The resulting number is calculated as:
/// (-1)^sign_bit * (words[0] * (2^64)^0 + words[1] * (2^64)^1 + ...)
static BigInt New(napi_env env, ///< Node-API environment
int sign_bit, ///< Sign bit. 1 if negative.
size_t word_count, ///< Number of words in array
const uint64_t* words ///< Array of words
);
static void CheckCast(napi_env env, napi_value value);
BigInt(); ///< Creates a new _empty_ BigInt instance.
BigInt(napi_env env,
napi_value value); ///< Wraps a Node-API value primitive.
int64_t Int64Value(bool* lossless)
const; ///< Converts a BigInt value to a 64-bit signed integer value.
uint64_t Uint64Value(bool* lossless)
const; ///< Converts a BigInt value to a 64-bit unsigned integer value.
size_t WordCount() const; ///< The number of 64-bit words needed to store
///< the result of ToWords().
/// Writes the contents of this BigInt to a specified memory location.
/// `sign_bit` must be provided and will be set to 1 if this BigInt is
/// negative.
/// `*word_count` has to be initialized to the length of the `words` array.
/// Upon return, it will be set to the actual number of words that would
/// be needed to store this BigInt (i.e. the return value of `WordCount()`).
void ToWords(int* sign_bit, size_t* word_count, uint64_t* words);
};
#endif // NAPI_VERSION > 5
#if (NAPI_VERSION > 4)
/// A JavaScript date value.
class Date : public Value {
public:
/// Creates a new Date value from a double primitive.
static Date New(napi_env env, ///< Node-API environment
double value ///< Number value
);
/// Creates a new Date value from a std::chrono::system_clock::time_point.
static Date New(
napi_env env, ///< Node-API environment
std::chrono::system_clock::time_point time_point ///< Time point value
);
static void CheckCast(napi_env env, napi_value value);
Date(); ///< Creates a new _empty_ Date instance.
Date(napi_env env, napi_value value); ///< Wraps a Node-API value primitive.
operator double() const; ///< Converts a Date value to double primitive
double ValueOf() const; ///< Converts a Date value to a double primitive.
};
#endif
/// A JavaScript string or symbol value (that can be used as a property name).
class Name : public Value {
public:
static void CheckCast(napi_env env, napi_value value);
Name(); ///< Creates a new _empty_ Name instance.
Name(napi_env env,
napi_value value); ///< Wraps a Node-API value primitive.
};
/// A JavaScript string value.
class String : public Name {
public:
/// Creates a new String value from a UTF-8 encoded C++ string.
static String New(napi_env env, ///< Node-API environment
const std::string& value ///< UTF-8 encoded C++ string
);
/// Creates a new String value from a UTF-16 encoded C++ string.
static String New(napi_env env, ///< Node-API environment
const std::u16string& value ///< UTF-16 encoded C++ string
);
/// Creates a new String value from a UTF-8 encoded C++ string view.
static String New(napi_env env, ///< Node-API environment
std::string_view value ///< UTF-8 encoded C++ string view
);
/// Creates a new String value from a UTF-8 encoded C string.
static String New(
napi_env env, ///< Node-API environment
const char* value ///< UTF-8 encoded null-terminated C string
);
/// Creates a new String value from a UTF-16 encoded C string.
static String New(
napi_env env, ///< Node-API environment
const char16_t* value ///< UTF-16 encoded null-terminated C string
);
/// Creates a new String value from a UTF-8 encoded C string with specified
/// length.
static String New(napi_env env, ///< Node-API environment
const char* value, ///< UTF-8 encoded C string (not
///< necessarily null-terminated)
size_t length ///< length of the string in bytes
);
/// Creates a new String value from a UTF-16 encoded C string with specified
/// length.
static String New(
napi_env env, ///< Node-API environment
const char16_t* value, ///< UTF-16 encoded C string (not necessarily
///< null-terminated)
size_t length ///< Length of the string in 2-byte code units
);
/// Creates a new String based on the original object's type.
///
/// `value` may be any of:
/// - const char* (encoded using UTF-8, null-terminated)
/// - const char16_t* (encoded using UTF-16-LE, null-terminated)
/// - std::string (encoded using UTF-8)
/// - std::u16string
template <typename T>
static String From(napi_env env, const T& value);
static void CheckCast(napi_env env, napi_value value);
String(); ///< Creates a new _empty_ String instance.
String(napi_env env,
napi_value value); ///< Wraps a Node-API value primitive.
operator std::string()
const; ///< Converts a String value to a UTF-8 encoded C++ string.
operator std::u16string()
const; ///< Converts a String value to a UTF-16 encoded C++ string.
std::string Utf8Value()
const; ///< Converts a String value to a UTF-8 encoded C++ string.
std::u16string Utf16Value()
const; ///< Converts a String value to a UTF-16 encoded C++ string.
};
namespace details {
// This overload set must mirror the non-template Symbol::For overloads.
struct string_convertible_probe {
static void select(const std::string&);
static void select(std::string_view);
static void select(const char*);
static void select(String);
static void select(napi_value);
};
template <typename T, typename = void>
struct has_unambiguous_string_convertible_overload : std::false_type {};
template <typename T>
struct has_unambiguous_string_convertible_overload<
T,
std::void_t<decltype(string_convertible_probe::select(std::declval<T>()))>>
: std::true_type {};
// Enable the template overload only for string-like arguments that have no
// unique best match among the non-template Symbol::For overloads.
//
// Exclude nullptr because it matches the pointer overloads equally well and
// cannot safely initialize a std::string_view.
template <typename T>
using enable_if_ambiguous_string_convertible_t =
std::enable_if_t<!std::is_null_pointer_v<std::decay_t<T>> &&
std::is_convertible_v<T, const std::string&> &&
std::is_convertible_v<T, std::string_view> &&
!has_unambiguous_string_convertible_overload<T>::value,
int>;
} // namespace details
/// A JavaScript symbol value.
class Symbol : public Name {
public:
/// Creates a new Symbol value with an optional description.
static Symbol New(
napi_env env, ///< Node-API environment
const char* description =
nullptr ///< Optional UTF-8 encoded null-terminated C string
/// describing the symbol
);
/// Creates a new Symbol value with a description.
static Symbol New(
napi_env env, ///< Node-API environment
const std::string&
description ///< UTF-8 encoded C++ string describing the symbol
);
/// Creates a new Symbol value with a description.
static Symbol New(
napi_env env, ///< Node-API environment
std::string_view
description ///< UTF-8 encoded C++ string view describing the symbol
);
/// Creates a new Symbol value with a description.
static Symbol New(napi_env env, ///< Node-API environment
String description ///< String value describing the symbol
);
/// Creates a new Symbol value with a description.
static Symbol New(
napi_env env, ///< Node-API environment
napi_value description ///< String value describing the symbol
);
/// Get a public Symbol (e.g. Symbol.iterator).
static MaybeOrValue<Symbol> WellKnown(napi_env, const std::string& name);
// Create a symbol in the global registry, UTF-8 Encoded cpp string
static MaybeOrValue<Symbol> For(napi_env env, const std::string& description);
// Create a symbol in the global registry, UTF-8 encoded cpp string view
static MaybeOrValue<Symbol> For(napi_env env, std::string_view description);
// Resolve otherwise ambiguous string-like arguments through the
// std::string_view overload
template <typename T,
details::enable_if_ambiguous_string_convertible_t<T&&> = 0>
static MaybeOrValue<Symbol> For(napi_env env, T&& description);
// Create a symbol in the global registry, C style string (null terminated)
static MaybeOrValue<Symbol> For(napi_env env, const char* description);
// Create a symbol in the global registry, String value describing the symbol
static MaybeOrValue<Symbol> For(napi_env env, String description);
// Create a symbol in the global registry, napi_value describing the symbol
static MaybeOrValue<Symbol> For(napi_env env, napi_value description);
static void CheckCast(napi_env env, napi_value value);
Symbol(); ///< Creates a new _empty_ Symbol instance.
Symbol(napi_env env,
napi_value value); ///< Wraps a Node-API value primitive.
};
class TypeTaggable : public Value {
public:
#if NAPI_VERSION >= 8
void TypeTag(const napi_type_tag* type_tag) const;
bool CheckTypeTag(const napi_type_tag* type_tag) const;
#endif // NAPI_VERSION >= 8
protected:
TypeTaggable();
TypeTaggable(napi_env env, napi_value value);
};
/// A JavaScript object value.
class Object : public TypeTaggable {
public:
/// Enables property and element assignments using indexing syntax.
///
/// This is a convenient helper to get and set object properties. As
/// getting and setting object properties may throw with JavaScript
/// exceptions, it is notable that these operations may fail.
/// When NODE_ADDON_API_ENABLE_MAYBE is defined, the process will abort
/// on JavaScript exceptions.
///
/// Example:
///
/// Napi::Value propertyValue = object1['A'];
/// object2['A'] = propertyValue;
/// Napi::Value elementValue = array[0];
/// array[1] = elementValue;
template <typename Key>
class PropertyLValue {
public:
/// Converts an L-value to a value.
operator Value() const;
/// Assigns a value to the property. The type of value can be
/// anything supported by `Object::Set`.
template <typename ValueType>
PropertyLValue& operator=(ValueType value);
/// Converts an L-value to a value. For convenience.
Value AsValue() const;
private:
PropertyLValue() = delete;
PropertyLValue(Object object, Key key);
napi_env _env;
napi_value _object;
Key _key;
friend class Napi::Object;
};
/// Creates a new Object value.
static Object New(napi_env env ///< Node-API environment
);
#ifdef NODE_API_EXPERIMENTAL_HAS_CREATE_OBJECT_WITH_PROPERTIES
/// Creates a new Object value with the given property names and values.
static Object New(
napi_env env, ///< Node-API environment
napi_value prototypeOrNull, ///< Prototype (Object) or null / empty Value
const std::vector<napi_value>& propertyNames, ///< Property names
const std::vector<napi_value>& propertyValues ///< Property values
);
#endif
static void CheckCast(napi_env env, napi_value value);
Object(); ///< Creates a new _empty_ Object instance.
Object(napi_env env,
napi_value value); ///< Wraps a Node-API value primitive.
/// Gets or sets a named property.
PropertyLValue<std::string> operator[](
const char* utf8name ///< UTF-8 encoded null-terminated property name
);
/// Gets or sets a named property.
PropertyLValue<std::string> operator[](
const std::string& utf8name ///< UTF-8 encoded property name
);
/// Gets or sets an indexed property or array element.
PropertyLValue<uint32_t> operator[](
uint32_t index /// Property / element index
);
/// Gets or sets an indexed property or array element.
PropertyLValue<Value> operator[](Value index /// Property / element index
) const;
/// Gets a named property.
MaybeOrValue<Value> operator[](
const char* utf8name ///< UTF-8 encoded null-terminated property name
) const;
/// Gets a named property.
MaybeOrValue<Value> operator[](
const std::string& utf8name ///< UTF-8 encoded property name
) const;
/// Gets an indexed property or array element.
MaybeOrValue<Value> operator[](uint32_t index ///< Property / element index
) const;