package.doc.errors.md Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of nan Show documentation
Native Abstractions for Node.js: C++ header for Node 0.8 -> 18 compatibility
There is a newer version: 2.19.0
## Errors

NAN includes helpers for creating, throwing and catching Errors as much of this functionality varies across the supported versions of V8 and must be abstracted.

Note that an Error object is simply a specialized form of `v8::Value`.

Also consult the V8 Embedders Guide section on [Exceptions](https://developers.google.com/v8/embed#exceptions) for more information.

 - Nan::Error()
 - Nan::RangeError()
 - Nan::ReferenceError()
 - Nan::SyntaxError()
 - Nan::TypeError()
 - Nan::ThrowError()
 - Nan::ThrowRangeError()
 - Nan::ThrowReferenceError()
 - Nan::ThrowSyntaxError()
 - Nan::ThrowTypeError()
 - Nan::FatalException()
 - Nan::ErrnoException()
 - Nan::TryCatch



### Nan::Error()

Create a new Error object using the [v8::Exception](https://v8docs.nodesource.com/node-8.16/da/d6a/classv8_1_1_exception.html) class in a way that is compatible across the supported versions of V8.

Note that an Error object is simply a specialized form of `v8::Value`.

Signature:

```c++
v8::Local Nan::Error(const char *msg);
v8::Local Nan::Error(v8::Local msg);
```



### Nan::RangeError()

Create a new RangeError object using the [v8::Exception](https://v8docs.nodesource.com/node-8.16/da/d6a/classv8_1_1_exception.html) class in a way that is compatible across the supported versions of V8.

Note that an RangeError object is simply a specialized form of `v8::Value`.

Signature:

```c++
v8::Local Nan::RangeError(const char *msg);
v8::Local Nan::RangeError(v8::Local msg);
```



### Nan::ReferenceError()

Create a new ReferenceError object using the [v8::Exception](https://v8docs.nodesource.com/node-8.16/da/d6a/classv8_1_1_exception.html) class in a way that is compatible across the supported versions of V8.

Note that an ReferenceError object is simply a specialized form of `v8::Value`.

Signature:

```c++
v8::Local Nan::ReferenceError(const char *msg);
v8::Local Nan::ReferenceError(v8::Local msg);
```



### Nan::SyntaxError()

Create a new SyntaxError object using the [v8::Exception](https://v8docs.nodesource.com/node-8.16/da/d6a/classv8_1_1_exception.html) class in a way that is compatible across the supported versions of V8.

Note that an SyntaxError object is simply a specialized form of `v8::Value`.

Signature:

```c++
v8::Local Nan::SyntaxError(const char *msg);
v8::Local Nan::SyntaxError(v8::Local msg);
```



### Nan::TypeError()

Create a new TypeError object using the [v8::Exception](https://v8docs.nodesource.com/node-8.16/da/d6a/classv8_1_1_exception.html) class in a way that is compatible across the supported versions of V8.

Note that an TypeError object is simply a specialized form of `v8::Value`.

Signature:

```c++
v8::Local Nan::TypeError(const char *msg);
v8::Local Nan::TypeError(v8::Local msg);
```



### Nan::ThrowError()

Throw an Error object (a specialized `v8::Value` as above) in the current context. If a `msg` is provided, a new Error object will be created.

Signature:

```c++
void Nan::ThrowError(const char *msg);
void Nan::ThrowError(v8::Local msg);
void Nan::ThrowError(v8::Local error);
```



### Nan::ThrowRangeError()

Throw an RangeError object (a specialized `v8::Value` as above) in the current context. If a `msg` is provided, a new RangeError object will be created.

Signature:

```c++
void Nan::ThrowRangeError(const char *msg);
void Nan::ThrowRangeError(v8::Local msg);
void Nan::ThrowRangeError(v8::Local error);
```



### Nan::ThrowReferenceError()

Throw an ReferenceError object (a specialized `v8::Value` as above) in the current context. If a `msg` is provided, a new ReferenceError object will be created.

Signature:

```c++
void Nan::ThrowReferenceError(const char *msg);
void Nan::ThrowReferenceError(v8::Local msg);
void Nan::ThrowReferenceError(v8::Local error);
```



### Nan::ThrowSyntaxError()

Throw an SyntaxError object (a specialized `v8::Value` as above) in the current context. If a `msg` is provided, a new SyntaxError object will be created.

Signature:

```c++
void Nan::ThrowSyntaxError(const char *msg);
void Nan::ThrowSyntaxError(v8::Local msg);
void Nan::ThrowSyntaxError(v8::Local error);
```



### Nan::ThrowTypeError()

Throw an TypeError object (a specialized `v8::Value` as above) in the current context. If a `msg` is provided, a new TypeError object will be created.

Signature:

```c++
void Nan::ThrowTypeError(const char *msg);
void Nan::ThrowTypeError(v8::Local msg);
void Nan::ThrowTypeError(v8::Local error);
```


### Nan::FatalException()

Replaces `node::FatalException()` which has a different API across supported versions of Node. For use with [`Nan::TryCatch`](#api_nan_try_catch).

Signature:

```c++
void Nan::FatalException(const Nan::TryCatch& try_catch);
```


### Nan::ErrnoException()

Replaces `node::ErrnoException()` which has a different API across supported versions of Node. 

Signature:

```c++
v8::Local Nan::ErrnoException(int errorno,
                                         const char* syscall = NULL,
                                         const char* message = NULL,
                                         const char* path = NULL);
```



### Nan::TryCatch

A simple wrapper around [`v8::TryCatch`](https://v8docs.nodesource.com/node-8.16/d4/dc6/classv8_1_1_try_catch.html) compatible with all supported versions of V8. Can be used as a direct replacement in most cases. See also [`Nan::FatalException()`](#api_nan_fatal_exception) for an internal use compatible with `node::FatalException`.

Signature:

```c++
class Nan::TryCatch {
 public:
  Nan::TryCatch();

  bool HasCaught() const;

  bool CanContinue() const;

  v8::Local ReThrow();

  v8::Local Exception() const;

  // Nan::MaybeLocal for older versions of V8
  v8::MaybeLocal StackTrace() const;

  v8::Local Message() const;

  void Reset();

  void SetVerbose(bool value);

  void SetCaptureMessage(bool value);
};
```