v8::MaybeLocal< T > Class Template Reference

#include <v8-local-handle.h>

Inheritance diagram for v8::MaybeLocal< T >:

Public Member Functions
	MaybeLocal ()
template<class S >
	MaybeLocal (Local< S > that)
bool	IsEmpty () const
template<class S >
bool	ToLocal (Local< S > *out) const
Local< T >	ToLocalChecked ()
template<class S >
Local< S >	FromMaybe (Local< S > default_value) const
template<class S >
MaybeLocal< S >	As () const

Static Public Member Functions
template<class S >
static MaybeLocal< T >	Cast (MaybeLocal< S > that)

Friends
template<typename S >
class	MaybeLocal

Detailed Description

template<class T>
class v8::MaybeLocal< T >

A MaybeLocal<> is a wrapper around Local<> that enforces a check whether the Local<> is empty before it can be used.

If an API method returns a MaybeLocal<>, 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, or because a TerminateExecution exception was thrown. In that case, an empty MaybeLocal is returned.

Examples

process.cc, and shell.cc.

Constructor & Destructor Documentation

MaybeLocal() [1/2]

template<class T >

v8::MaybeLocal< T >::MaybeLocal ( )

inline

MaybeLocal() [2/2]

template<class T >

template<class S >

v8::MaybeLocal< T >::MaybeLocal ( Local< S >  that )

inline

Member Function Documentation

As()

template<class T >

template<class S >

MaybeLocal< S > v8::MaybeLocal< T >::As ( ) const

inline

Calling this is equivalent to MaybeLocal<S>::Cast(). In particular, this is only valid if the handle actually refers to a value of the target type.

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Cast()

template<class T >

template<class S >

static MaybeLocal< T > v8::MaybeLocal< T >::Cast ( MaybeLocal< S >  that )

inlinestatic

Cast a handle to a subclass, e.g. MaybeLocal<Value> to MaybeLocal<Object>. This is only valid if the handle actually refers to a value of the target type.

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FromMaybe()

template<class T >

template<class S >

Local< S > v8::MaybeLocal< T >::FromMaybe ( Local< S >  default_value ) const

inline

Converts this MaybeLocal<> to a Local<>, using a default value if this MaybeLocal<> is empty.

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IsEmpty()

template<class T >

bool v8::MaybeLocal< T >::IsEmpty ( ) const

inline

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ToLocal()

template<class T >

template<class S >

bool v8::MaybeLocal< T >::ToLocal ( Local< S > *  out ) const

inline

Converts this MaybeLocal<> to a Local<>. If this MaybeLocal<> is empty, |false| is returned and |out| is assigned with nullptr.

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ToLocalChecked()

template<class T >

Local< T > v8::MaybeLocal< T >::ToLocalChecked ( )

inline

Converts this MaybeLocal<> to a Local<>. If this MaybeLocal<> is empty, V8 will crash the process.

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Friends And Related Function Documentation

MaybeLocal

template<class T >

template<typename S >

friend class MaybeLocal

friend

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The documentation for this class was generated from the following file:

• include/v8-local-handle.h