QScriptEngine Class Reference

The QScriptEngine class provides an environment for evaluating Qt Script code. More...

#include <qscriptengine.h>

Inheritance diagram for QScriptEngine:

Public Types
typedef void(*	DemarshalFunction) (const QScriptValue &, void *)
typedef QScriptValue(*	FunctionSignature) (QScriptContext *, QScriptEngine *)
typedef QScriptValue(*	FunctionWithArgSignature) (QScriptContext *, QScriptEngine *, void *)
typedef QScriptValue(*	MarshalFunction) (QScriptEngine *, const void *)
enum	QObjectWrapOption {   ExcludeChildObjects = 0x0001, ExcludeSuperClassMethods = 0x0002, ExcludeSuperClassProperties = 0x0004, ExcludeSuperClassContents = 0x0006,   SkipMethodsInEnumeration = 0x0008, ExcludeDeleteLater = 0x0010, ExcludeSlots = 0x0020, AutoCreateDynamicProperties = 0x0100,   PreferExistingWrapperObject = 0x0200 }
	These flags specify options when wrapping a QObject pointer with newQObject(). More...
enum	ValueOwnership { QtOwnership, ScriptOwnership, AutoOwnership }
	This enum specifies the ownership when wrapping a C++ value, e. More...

Signals
void	signalHandlerException (const QScriptValue &exception)
	This signal is emitted when a script function connected to a signal causes an exception. More...
Signals inherited from QObject
void	destroyed (QObject *=0)
	This signal is emitted immediately before the object obj is destroyed, and can not be blocked. More...

Public Functions
void	abortEvaluation (const QScriptValue &result=QScriptValue())
	Aborts any script evaluation currently taking place in this engine. More...
QScriptEngineAgent *	agent () const
	Returns the agent currently installed on this engine, or 0 if no agent is installed. More...
QStringList	availableExtensions () const
	Returns a list naming the available extensions that can be imported using the importExtension() function. More...
bool	canEvaluate (const QString &program) const
	Returns true if program can be evaluated; i. More...
void	clearExceptions ()
	Clears any uncaught exceptions in this engine. More...
void	collectGarbage ()
	Runs the garbage collector. More...
QScriptContext *	currentContext () const
	Returns the current context. More...
QScriptValue	defaultPrototype (int metaTypeId) const
	Returns the default prototype associated with the given metaTypeId, or an invalid QScriptValue if no default prototype has been set. More...
QScriptValue	evaluate (const QString &program, const QString &fileName=QString(), int lineNumber=1)
	Evaluates program, using lineNumber as the base line number, and returns the result of the evaluation. More...
QScriptValue	evaluate (const QScriptProgram &program)
	Evaluates the given program and returns the result of the evaluation. More...
template<typename T >
T	fromScriptValue (const QScriptValue &value)
	Returns the given value converted to the template type T. More...
QScriptValue	globalObject () const
	Returns this engine's Global Object. More...
bool	hasUncaughtException () const
	Returns true if the last script evaluation resulted in an uncaught exception; otherwise returns false. More...
QStringList	importedExtensions () const
	Returns a list naming the extensions that have been imported using the importExtension() function. More...
QScriptValue	importExtension (const QString &extension)
	Imports the given extension into this QScriptEngine. More...
void	installTranslatorFunctions (const QScriptValue &object=QScriptValue())
	Installs translator functions on the given object, or on the Global Object if no object is specified. More...
bool	isEvaluating () const
	Returns true if this engine is currently evaluating a script, otherwise returns false. More...
QScriptValue	newActivationObject ()
QScriptValue	newArray (uint length=0)
	Creates a QtScript object of class Array with the given length. More...
QScriptValue	newDate (qsreal value)
	Creates a QtScript object of class Date with the given value (the number of milliseconds since 01 January 1970, UTC). More...
QScriptValue	newDate (const QDateTime &value)
	Creates a QtScript object of class Date from the given value. More...
QScriptValue	newFunction (FunctionSignature signature, int length=0)
	Creates a QScriptValue that wraps a native (C++) function. More...
QScriptValue	newFunction (FunctionSignature signature, const QScriptValue &prototype, int length=0)
	Creates a constructor function from fun, with the given length. More...
QScriptValue	newFunction (FunctionWithArgSignature signature, void *arg)
QScriptValue	newObject ()
	Creates a QtScript object of class Object. More...
QScriptValue	newObject (QScriptClass *scriptClass, const QScriptValue &data=QScriptValue())
	Creates a QtScript Object of the given class, scriptClass. More...
QScriptValue	newQMetaObject (const QMetaObject *metaObject, const QScriptValue &ctor=QScriptValue())
	Creates a QtScript object that represents a QObject class, using the the given metaObject and constructor ctor. More...
QScriptValue	newQObject (QObject *object, ValueOwnership ownership=QtOwnership, const QObjectWrapOptions &options=0)
	Creates a QtScript object that wraps the given QObject object, using the given ownership. More...
QScriptValue	newQObject (const QScriptValue &scriptObject, QObject *qtObject, ValueOwnership ownership=QtOwnership, const QObjectWrapOptions &options=0)
	Initializes the given scriptObject to hold the given qtObject, and returns the scriptObject. More...
QScriptValue	newRegExp (const QRegExp &regexp)
	Creates a QtScript object of class RegExp with the given regexp. More...
QScriptValue	newRegExp (const QString &pattern, const QString &flags)
	Creates a QtScript object of class RegExp with the given pattern and flags. More...
QScriptValue	newVariant (const QVariant &value)
	Creates a QtScript object holding the given variant value. More...
QScriptValue	newVariant (const QScriptValue &object, const QVariant &value)
	Initializes the given Qt Script object to hold the given variant value, and returns the object. More...
QScriptValue	nullValue ()
	Returns a QScriptValue of the primitive type Null. More...
QScriptValue	objectById (qint64 id) const
	Returns the object with the given id, or an invalid QScriptValue if there is no object with that id. More...
void	popContext ()
	Pops the current execution context and restores the previous one. More...
int	processEventsInterval () const
	Returns the interval in milliseconds between calls to QCoreApplication::processEvents() while the interpreter is running. More...
QScriptContext *	pushContext ()
	Enters a new execution context and returns the associated QScriptContext object. More...
	QScriptEngine ()
	Constructs a QScriptEngine object. More...
	QScriptEngine (QObject *parent)
	Constructs a QScriptEngine object with the given parent. More...
void	reportAdditionalMemoryCost (int size)
	Reports an additional memory cost of the given size, measured in bytes, to the garbage collector. More...
template<class T >
QScriptValue	scriptValueFromQMetaObject ()
	Creates a QScriptValue that represents the Qt class T. More...
void	setAgent (QScriptEngineAgent *agent)
	Installs the given agent on this engine. More...
void	setDefaultPrototype (int metaTypeId, const QScriptValue &prototype)
	Sets the default prototype of the C++ type identified by the given metaTypeId to prototype. More...
void	setGlobalObject (const QScriptValue &object)
	Sets this engine's Global Object to be the given object. More...
void	setProcessEventsInterval (int interval)
	Sets the interval between calls to QCoreApplication::processEvents to interval milliseconds. More...
QScriptValue	toObject (const QScriptValue &value)
	Converts the given value to an object, if such a conversion is possible; otherwise returns an invalid QScriptValue. More...
template<typename T >
QScriptValue	toScriptValue (const T &value)
	Creates a QScriptValue with the given value. More...
QScriptString	toStringHandle (const QString &str)
	Returns a handle that represents the given string, str. More...
QScriptValue	uncaughtException () const
	Returns the current uncaught exception, or an invalid QScriptValue if there is no uncaught exception. More...
QStringList	uncaughtExceptionBacktrace () const
	Returns a human-readable backtrace of the last uncaught exception. More...
int	uncaughtExceptionLineNumber () const
	Returns the line number where the last uncaught exception occurred. More...
QScriptValue	undefinedValue ()
	Returns a QScriptValue of the primitive type Undefined. More...
virtual	~QScriptEngine ()
	Destroys this QScriptEngine. More...
Public Functions inherited from QObject
bool	blockSignals (bool b)
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it). More...
const QObjectList &	children () const
	Returns a list of child objects. More...
bool	connect (const QObject *sender, const char *signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const
bool	disconnect (const char *signal=0, const QObject *receiver=0, const char *member=0)
bool	disconnect (const QObject *receiver, const char *member=0)
void	dumpObjectInfo ()
	Dumps information about signal connections, etc. More...
void	dumpObjectTree ()
	Dumps a tree of children to the debug output. More...
QList< QByteArray >	dynamicPropertyNames () const
	Returns the names of all properties that were dynamically added to the object using setProperty(). More...
virtual bool	event (QEvent *)
	This virtual function receives events to an object and should return true if the event e was recognized and processed. More...
virtual bool	eventFilter (QObject *, QEvent *)
	Filters events if this object has been installed as an event filter for the watched object. More...
template<typename T >
T	findChild (const QString &aName=QString()) const
	Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. More...
template<typename T >
QList< T >	findChildren (const QString &aName=QString()) const
	Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. More...
template<typename T >
QList< T >	findChildren (const QRegExp &re) const
bool	inherits (const char *classname) const
	Returns true if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns false. More...
void	installEventFilter (QObject *)
	Installs an event filter filterObj on this object. More...
bool	isWidgetType () const
	Returns true if the object is a widget; otherwise returns false. More...
void	killTimer (int id)
	Kills the timer with timer identifier, id. More...
virtual const QMetaObject *	metaObject () const
	Returns a pointer to the meta-object of this object. More...
void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children. More...
QString	objectName () const
QObject *	parent () const
	Returns a pointer to the parent object. More...
QVariant	property (const char *name) const
	Returns the value of the object's name property. More...
Q_INVOKABLE	QObject (QObject *parent=0)
	Constructs an object with parent object parent. More...
void	removeEventFilter (QObject *)
	Removes an event filter object obj from this object. More...
void	setObjectName (const QString &name)
void	setParent (QObject *)
	Makes the object a child of parent. More...
bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value. More...
void	setUserData (uint id, QObjectUserData *data)
bool	signalsBlocked () const
	Returns true if signals are blocked; otherwise returns false. More...
int	startTimer (int interval)
	Starts a timer and returns a timer identifier, or returns zero if it could not start a timer. More...
QThread *	thread () const
	Returns the thread in which the object lives. More...
QObjectUserData *	userData (uint id) const
virtual	~QObject ()
	Destroys the object, deleting all its child objects. More...

Static Public Functions
static QScriptSyntaxCheckResult	checkSyntax (const QString &program)
	Checks the syntax of the given program. More...
Static Public Functions inherited from QObject
static bool	connect (const QObject *sender, const char *signal, const QObject *receiver, const char *member, Qt::ConnectionType=Qt::AutoConnection)
	Creates a connection of the given type from the signal in the sender object to the method in the receiver object. More...
static bool	connect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)
static bool	disconnect (const QObject *sender, const char *signal, const QObject *receiver, const char *member)
	Disconnects signal in object sender from method in object receiver. More...
static bool	disconnect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &member)
static uint	registerUserData ()
static QString	tr (const char *sourceText, const char *comment=0, int n=-1)
static QString	trUtf8 (const char *sourceText, const char *comment=0, int n=-1)

Protected Functions
	QScriptEngine (QScriptEnginePrivate &dd, QObject *parent=0)
Protected Functions inherited from QObject
virtual void	childEvent (QChildEvent *)
	This event handler can be reimplemented in a subclass to receive child events. More...
virtual void	connectNotify (const char *signal)
	This virtual function is called when something has been connected to signal in this object. More...
virtual void	customEvent (QEvent *)
	This event handler can be reimplemented in a subclass to receive custom events. More...
virtual void	disconnectNotify (const char *signal)
	This virtual function is called when something has been disconnected from signal in this object. More...
	QObject (QObjectPrivate &dd, QObject *parent=0)
int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal. More...
QObject *	sender () const
	Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns 0. More...
int	senderSignalIndex () const
virtual void	timerEvent (QTimerEvent *)
	This event handler can be reimplemented in a subclass to receive timer events for the object. More...

Private Functions
bool	convert (const QScriptValue &value, int type, void *ptr)
QScriptValue	create (int type, const void *ptr)
void	registerCustomType (int type, MarshalFunction mf, DemarshalFunction df, const QScriptValue &prototype)

Static Private Functions
static bool	convertV2 (const QScriptValue &value, int type, void *ptr)

Friends
void	qScriptRegisterMetaType_helper (QScriptEngine *, int, MarshalFunction, DemarshalFunction, const QScriptValue &)
bool	qscriptvalue_cast_helper (const QScriptValue &, int, void *)
QScriptValue	qScriptValueFromValue_helper (QScriptEngine *, int, const void *)

Related Functions
(Note that these are not member functions.)
	FunctionSignature
	FunctionWithArgSignature
bool	qScriptConnect (QObject *sender, const char *signal, const QScriptValue &receiver, const QScriptValue &function)
	Creates a connection from the signal in the sender to the given function. More...
bool	qScriptDisconnect (QObject *sender, const char *signal, const QScriptValue &receiver, const QScriptValue &function)
	Disconnects the signal in the sender from the given (receiver, function) pair. More...
int	qScriptRegisterMetaType (QScriptEngine *engine, QScriptValue(*toScriptValue)(QScriptEngine *, const T &t), void(*fromScriptValue)(const QScriptValue &, T &t), const QScriptValue &prototype=QScriptValue())
int	qScriptRegisterSequenceMetaType (QScriptEngine *engine, const QScriptValue &prototype=QScriptValue())
QScriptValue	qScriptValueFromQMetaObject (QScriptEngine *engine)
QScriptValue	qScriptValueFromSequence (QScriptEngine *engine, const Container &container)
QScriptValue	qScriptValueFromValue (QScriptEngine *engine, const T &value)
void	qScriptValueToSequence (const QScriptValue &value, Container &container)
	Copies the elements in the sequence specified by value to the given container of template type Container. More...
T	qScriptValueToValue (const QScriptValue &value)
	Returns the given value converted to the template type T. More...
Related Functions inherited from QObject
T	qFindChildqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QRegExp &regExp)()
T *	qobject_cast (QObject *object)
	QObjectList
void *	qt_find_obj_child (QObject *parent, const char *type, const QString &name)
	Returns a pointer to the object named name that inherits type and with a given parent. More...

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	Schedules this object for deletion. More...
Static Public Variables inherited from QObject
static const QMetaObject	staticMetaObject
	This variable stores the meta-object for the class. More...
Protected Variables inherited from QObject
QScopedPointer< QObjectData >	d_ptr
Static Protected Variables inherited from QObject
static const QMetaObject	staticQtMetaObject

Detailed Description

The QScriptEngine class provides an environment for evaluating Qt Script code.

Since

4.3

Note

This class or function is reentrant.

See the QtScript documentation for information about the Qt Script language, and how to get started with scripting your C++ application.

Evaluating Scripts

Use evaluate() to evaluate script code; this is the C++ equivalent of the built-in script function eval().

QScriptEngine myEngine;
QScriptValue three = myEngine.evaluate("1 + 2");

evaluate() returns a QScriptValue that holds the result of the evaluation. The QScriptValue class provides functions for converting the result to various C++ types (e.g. QScriptValue::toString() and QScriptValue::toNumber()).

The following code snippet shows how a script function can be defined and then invoked from C++ using QScriptValue::call():

QScriptValue fun = myEngine.evaluate("(function(a, b) { return a + b; })");
QScriptValueList args;
args << 1 << 2;
QScriptValue threeAgain = fun.call(QScriptValue(), args);

As can be seen from the above snippets, a script is provided to the engine in the form of a string. One common way of loading scripts is by reading the contents of a file and passing it to evaluate():

QString fileName = "helloworld.qs";
QFile scriptFile(fileName);
if (!scriptFile.open(QIODevice::ReadOnly))
    // handle error
QTextStream stream(&scriptFile);
QString contents = stream.readAll();
scriptFile.close();
myEngine.evaluate(contents, fileName);

Here we pass the name of the file as the second argument to evaluate(). This does not affect evaluation in any way; the second argument is a general-purpose string that is used to identify the script for debugging purposes (for example, our filename will now show up in any uncaughtExceptionBacktrace() involving the script).

Engine Configuration

The globalObject() function returns the Global Object associated with the script engine. Properties of the Global Object are accessible from any script code (i.e. they are global variables). Typically, before evaluating "user" scripts, you will want to configure a script engine by adding one or more properties to the Global Object:

myEngine.globalObject().setProperty("myNumber", 123);
...
QScriptValue myNumberPlusOne = myEngine.evaluate("myNumber + 1");

Adding custom properties to the scripting environment is one of the standard means of providing a scripting API that is specific to your application. Usually these custom properties are objects created by the newQObject() or newObject() functions, or constructor functions created by newFunction().

Script Exceptions

evaluate() can throw a script exception (e.g. due to a syntax error); in that case, the return value is the value that was thrown (typically an Error object). You can check whether the evaluation caused an exception by calling hasUncaughtException(). In that case, you can call toString() on the error object to obtain an error message. The current uncaught exception is also available through uncaughtException(). Calling clearExceptions() will cause any uncaught exceptions to be cleared.

QScriptValue result = myEngine.evaluate(...);
if (myEngine.hasUncaughtException()) {
    int line = myEngine.uncaughtExceptionLineNumber();
    qDebug() << "uncaught exception at line" << line << ":" << result.toString();
}

The checkSyntax() function can be used to determine whether code can be usefully passed to evaluate().

Script Object Creation

Use newObject() to create a standard Qt Script object; this is the C++ equivalent of the script statement new Object(). You can use the object-specific functionality in QScriptValue to manipulate the script object (e.g. QScriptValue::setProperty()). Similarly, use newArray() to create a Qt Script array object. Use newDate() to create a Date object, and newRegExp() to create a RegExp object.

QObject Integration

Use newQObject() to wrap a QObject (or subclass) pointer. newQObject() returns a proxy script object; properties, children, and signals and slots of the QObject are available as properties of the proxy object. No binding code is needed because it is done dynamically using the Qt meta object system.

QPushButton button;
QScriptValue scriptButton = myEngine.newQObject(&button);
myEngine.globalObject().setProperty("button", scriptButton);

myEngine.evaluate("button.checkable = true");

qDebug() << scriptButton.property("checkable").toBoolean();
scriptButton.property("show").call(); // call the show() slot

Use qScriptConnect() to connect a C++ signal to a script function; this is the Qt Script equivalent of QObject::connect(). When a script function is invoked in response to a C++ signal, it can cause a script exception; you can connect to the signalHandlerException() signal to catch such an exception.

Use newQMetaObject() to wrap a QMetaObject; this gives you a "script representation" of a QObject-based class. newQMetaObject() returns a proxy script object; enum values of the class are available as properties of the proxy object. You can also specify a function that will be used to construct objects of the class (e.g. when the constructor is invoked from a script). For classes that have a "standard" Qt constructor, Qt Script can provide a default script constructor for you; see scriptValueFromQMetaObject().

For more information about QObject integration, see Making Applications Scriptable

++-Types

Support for Custom C++ Types

Use newVariant() to wrap a QVariant. This can be used to store values of custom (non-QObject) C++ types that have been registered with the Qt meta-type system. To make such types scriptable, you typically associate a prototype (delegate) object with the C++ type by calling setDefaultPrototype(); the prototype object defines the scripting API for the C++ type. Unlike the QObject integration, there is no automatic binding possible here; i.e. you have to create the scripting API yourself, for example by using the QScriptable class.

Use fromScriptValue() to cast from a QScriptValue to another type, and toScriptValue() to create a QScriptValue from another value. You can specify how the conversion of C++ types is to be performed with qScriptRegisterMetaType() and qScriptRegisterSequenceMetaType(). By default, Qt Script will use QVariant to store values of custom types.

Importing Extensions

Use importExtension() to import plugin-based extensions into the engine. Call availableExtensions() to obtain a list naming all the available extensions, and importedExtensions() to obtain a list naming only those extensions that have been imported.

Call pushContext() to open up a new variable scope, and popContext() to close the current scope. This is useful if you are implementing an extension that evaluates script code containing temporary variable definitions (e.g. var foo = 123;) that are safe to discard when evaluation has completed.

Native Functions

Use newFunction() to wrap native (C++) functions, including constructors for your own custom types, so that these can be invoked from script code. Such functions must have the signature QScriptEngine::FunctionSignature. You may then pass the function as argument to newFunction(). Here is an example of a function that returns the sum of its first two arguments:

QScriptValue myAdd(QScriptContext *context, QScriptEngine *engine)
{
   QScriptValue a = context->argument(0);
   QScriptValue b = context->argument(1);
   return a.toNumber() + b.toNumber();
}

To expose this function to script code, you can set it as a property of the Global Object:

QScriptValue fun = myEngine.newFunction(myAdd);
myEngine.globalObject().setProperty("myAdd", fun);

Once this is done, script code can call your function in the exact same manner as a "normal" script function:

QScriptValue result = myEngine.evaluate("myAdd(myNumber, 1)");

Long-running Scripts

If you need to evaluate possibly long-running scripts from the main (GUI) thread, you should first call setProcessEventsInterval() to make sure that the GUI stays responsive. You can abort a currently running script by calling abortEvaluation(). You can determine whether an engine is currently running a script by calling isEvaluating().

Garbage Collection

Qt Script objects may be garbage collected when they are no longer referenced. There is no guarantee as to when automatic garbage collection will take place.

The collectGarbage() function can be called to explicitly request garbage collection.

The reportAdditionalMemoryCost() function can be called to indicate that a Qt Script object occupies memory that isn't managed by the scripting environment. Reporting the additional cost makes it more likely that the garbage collector will be triggered. This can be useful, for example, when many custom, native Qt Script objects are allocated.

/Tracing-Facilities

Core Debugging/Tracing Facilities

Since Qt 4.4, you can be notified of events pertaining to script execution (e.g. script function calls and statement execution) through the QScriptEngineAgent interface; see the setAgent() function. This can be used to implement debugging and profiling of a QScriptEngine.

See also

QScriptValue, QScriptContext, QScriptEngineAgent

Definition at line 104 of file qscriptengine.h.

Typedefs

DemarshalFunction

QScriptEngine::DemarshalFunction

Warning

This function is not part of the public interface.

Definition at line 208 of file qscriptengine.h.

FunctionSignature

typedef QScriptValue(* QScriptEngine::FunctionSignature) (QScriptContext *, QScriptEngine *)

Definition at line 165 of file qscriptengine.h.

FunctionWithArgSignature

typedef QScriptValue(* QScriptEngine::FunctionWithArgSignature) (QScriptContext *, QScriptEngine *, void *)

Definition at line 166 of file qscriptengine.h.

MarshalFunction

QScriptEngine::MarshalFunction

Warning

This function is not part of the public interface.

Definition at line 207 of file qscriptengine.h.

Enumerations

QObjectWrapOption

enum QScriptEngine::QObjectWrapOption

These flags specify options when wrapping a QObject pointer with newQObject().

• ExcludeChildObjects The script object will not expose child objects as properties.
• ExcludeSuperClassMethods The script object will not expose signals and slots inherited from the superclass.
• ExcludeSuperClassProperties The script object will not expose properties inherited from the superclass.
• ExcludeSuperClassContents Shorthand form for ExcludeSuperClassMethods | ExcludeSuperClassProperties
• ExcludeDeleteLater The script object will not expose the QObject::deleteLater() slot.
• ExcludeSlots The script object will not expose the QObject's slots.
• AutoCreateDynamicProperties Properties that don't already exist in the QObject will be created as dynamic properties of that object, rather than as properties of the script object.
• PreferExistingWrapperObject If a wrapper object with the requested configuration already exists, return that object.
• SkipMethodsInEnumeration Don't include methods (signals and slots) when enumerating the object's properties.

Enumerator
ExcludeChildObjects
ExcludeSuperClassMethods
ExcludeSuperClassProperties
ExcludeSuperClassContents
SkipMethodsInEnumeration
ExcludeDeleteLater
ExcludeSlots
AutoCreateDynamicProperties
PreferExistingWrapperObject

Definition at line 119 of file qscriptengine.h.

                           {
        ExcludeChildObjects = 0x0001,
        ExcludeSuperClassMethods = 0x0002,
        ExcludeSuperClassProperties = 0x0004,
        ExcludeSuperClassContents = 0x0006,
        SkipMethodsInEnumeration = 0x0008,
        ExcludeDeleteLater = 0x0010,
        ExcludeSlots = 0x0020,

        AutoCreateDynamicProperties = 0x0100,
        PreferExistingWrapperObject = 0x0200
    };

ValueOwnership

enum QScriptEngine::ValueOwnership

This enum specifies the ownership when wrapping a C++ value, e.

g. by using newQObject().

\arg \b QtOwnership The standard Qt ownership rules apply, i.e. the
associated object will never be explicitly deleted by the script
engine. This is the default. (QObject ownership is explained in
<b>Object Trees & Ownership</b>.)

\arg \b ScriptOwnership The value is owned by the script
environment. The associated data will be deleted when appropriate
(i.e. after the garbage collector has discovered that there are no
more live references to the value).

\arg \b AutoOwnership If the associated object has a parent, the Qt
ownership rules apply (QtOwnership); otherwise, the object is
owned by the script environment (ScriptOwnership).

Enumerator
QtOwnership
ScriptOwnership
AutoOwnership

Definition at line 113 of file qscriptengine.h.

                        {
        QtOwnership,
        ScriptOwnership,
        AutoOwnership
    };

Constructors and Destructors

QScriptEngine() [1/3]

QScriptEngine::QScriptEngine

(

)

Constructs a QScriptEngine object.

The globalObject() is initialized to have properties as described in ECMA-262, Section 15.1.

Definition at line 1984 of file qscriptengine.cpp.

Referenced by QScriptEnginePrivate::toStringHandle().

    : QObject(*new QScriptEnginePrivate, 0)
{
}

QScriptEngine() [2/3]

QScriptEngine::QScriptEngine ( QObject *  parent )

explicit

Constructs a QScriptEngine object with the given parent.

The globalObject() is initialized to have properties as described in ECMA-262, Section 15.1.

Definition at line 1996 of file qscriptengine.cpp.

    : QObject(*new QScriptEnginePrivate, parent)
{
}

~QScriptEngine()

QScriptEngine::~QScriptEngine ( )

virtual

Destroys this QScriptEngine.

Definition at line 2012 of file qscriptengine.cpp.

{
#ifdef QT_NO_QOBJECT
    delete d_ptr;
    d_ptr = 0;
#endif
}

QScriptEngine() [3/3]

QScriptEngine::QScriptEngine ( QScriptEnginePrivate &  dd, QObject *  parent = 0  )

protected

Warning

This function is not part of the public interface.

Definition at line 2003 of file qscriptengine.cpp.

    : QObject(dd, parent)
{
}

Functions

abortEvaluation()

void QScriptEngine::abortEvaluation

(

const QScriptValue &

result = QScriptValue()

)

Aborts any script evaluation currently taking place in this engine.

Since

4.4

The given result is passed back as the result of the evaluation (i.e. it is returned from the call to evaluate() being aborted).

If the engine isn't evaluating a script (i.e. isEvaluating() returns false), this function does nothing.

Call this function if you need to abort a running script for some reason, e.g. when you have detected that the script has been running for several seconds without completing.

See also

evaluate(), isEvaluating(), setProcessEventsInterval()

Definition at line 4216 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    if (!isEvaluating())
        return;
    d->abortResult = result;
    d->timeoutChecker()->setShouldAbort(true);
    JSC::throwError(d->currentFrame, JSC::createInterruptedExecutionException(&d->currentFrame->globalData()).toObject(d->currentFrame));
}

agent()

QScriptEngineAgent * QScriptEngine::agent

(

)

const

Returns the agent currently installed on this engine, or 0 if no agent is installed.

Since

4.4

See also

setAgent()

Definition at line 4353 of file qscriptengine.cpp.

Referenced by QScriptDebuggerBackend::detach(), popContext(), QScriptDeclarativeClass::pushCleanContext(), pushContext(), and setAgent().

{
    Q_D(const QScriptEngine);
    return d->activeAgent;
}

availableExtensions()

QStringList QScriptEngine::availableExtensions

(

)

const

Returns a list naming the available extensions that can be imported using the importExtension() function.

Since

4.4

This list includes extensions that have been imported.

See also

importExtension(), importedExtensions()

Definition at line 3754 of file qscriptengine.cpp.

{
#if defined(QT_NO_QOBJECT) || defined(QT_NO_LIBRARY) || defined(QT_NO_SETTINGS)
    return QStringList();
#else
    QCoreApplication *app = QCoreApplication::instance();
    if (!app)
        return QStringList();

    QSet<QString> result;

    QObjectList staticPlugins = QPluginLoader::staticInstances();
    for (int i = 0; i < staticPlugins.size(); ++i) {
        QScriptExtensionInterface *iface;
        iface = qobject_cast<QScriptExtensionInterface*>(staticPlugins.at(i));
        if (iface) {
            QStringList keys = iface->keys();
            for (int j = 0; j < keys.count(); ++j)
                result << keys.at(j);
        }
    }

    QStringList libraryPaths = app->libraryPaths();
    for (int i = 0; i < libraryPaths.count(); ++i) {
        QString libPath = libraryPaths.at(i) + QDir::separator() + QLatin1String("script");
        QDir dir(libPath);
        if (!dir.exists())
            continue;

        // look for C++ plugins
        QFileInfoList files = dir.entryInfoList(QDir::Files);
        for (int j = 0; j < files.count(); ++j) {
            QFileInfo entry = files.at(j);
            QString filePath = entry.canonicalFilePath();
            QPluginLoader loader(filePath);
            QScriptExtensionInterface *iface;
            iface = qobject_cast<QScriptExtensionInterface*>(loader.instance());
            if (iface) {
                QStringList keys = iface->keys();
                for (int k = 0; k < keys.count(); ++k)
                    result << keys.at(k);
            }
        }

        // look for scripts
        QString initDotJs = QLatin1String("__init__.js");
        QList<QFileInfo> stack;
        stack << dir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);
        while (!stack.isEmpty()) {
            QFileInfo entry = stack.takeLast();
            QDir dd(entry.canonicalFilePath());
            if (dd.exists(initDotJs)) {
                QString rpath = dir.relativeFilePath(dd.canonicalPath());
                QStringList components = rpath.split(QLatin1Char('/'));
                result << components.join(QLatin1String("."));
                stack << dd.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);
            }
        }
    }

    QStringList lst = result.toList();
    qSort(lst);
    return lst;
#endif
}

canEvaluate()

bool QScriptEngine::canEvaluate

(

const QString &

program

)

const

Returns true if program can be evaluated; i.

e. the code is sufficient to determine whether it appears to be a syntactically correct program, or contains a syntax error.

This function returns false if program is incomplete; i.e. the input is syntactically correct up to the point where the input is terminated.

Note that this function only does a static check of program; e.g. it does not check whether references to variables are valid, and so on.

A typical usage of canEvaluate() is to implement an interactive interpreter for QtScript. The user is repeatedly queried for individual lines of code; the lines are concatened internally, and only when canEvaluate() returns true for the resulting program is it passed to evaluate().

The following are some examples to illustrate the behavior of canEvaluate(). (Note that all example inputs are assumed to have an explicit newline as their last character, since otherwise the QtScript parser would automatically insert a semi-colon character at the end of the input, and this could cause canEvaluate() to produce different results.)

Given the input

if (hello && world)
    print("hello world");

canEvaluate() will return true, since the program appears to be complete.

Given the input

if (hello &&

canEvaluate() will return false, since the if-statement is not complete, but is syntactically correct so far.

Given the input

0 = 0

canEvaluate() will return true, but evaluate() will throw a SyntaxError given the same input.

Given the input

./test.js

canEvaluate() will return true, even though the code is clearly not syntactically valid QtScript code. evaluate() will throw a SyntaxError when this code is evaluated.

Given the input

foo["bar"]

canEvaluate() will return true, but evaluate() will throw a ReferenceError if foo is not defined in the script environment.

See also

evaluate(), checkSyntax()

Definition at line 2592 of file qscriptengine.cpp.

{
    return QScriptEnginePrivate::canEvaluate(program);
}

checkSyntax()

QScriptSyntaxCheckResult QScriptEngine::checkSyntax ( const QString &  program )

static

Checks the syntax of the given program.

Since

4.5

Returns a QScriptSyntaxCheckResult object that contains the result of the check.

Definition at line 2614 of file qscriptengine.cpp.

Referenced by QScriptDebuggerConsoleGlobalObject::checkSyntax(), QScriptDebuggerConsole::consumeInput(), QScriptDebuggerLocalsItemDelegate::eventFilter(), QScriptBreakpointsItemDelegate::eventFilter(), QScriptDebuggerLocalsItemDelegate::setModelData(), QScriptBreakpointsItemDelegate::setModelData(), QScriptDebuggerLocalsItemDelegate::validateInput(), and QScriptBreakpointsItemDelegate::validateInput().

{
    return QScriptEnginePrivate::checkSyntax(program);
}

clearExceptions()

void QScriptEngine::clearExceptions

(

)

Clears any uncaught exceptions in this engine.

Since

4.4

See also

hasUncaughtException()

Definition at line 2970 of file qscriptengine.cpp.

Referenced by QScriptDebuggerBackend::doPendingEvaluate(), QDeclarativeQtScriptExpression::eval(), QScriptDebuggerCommandExecutor::execute(), QDeclarativeInclude::finished(), QScriptDebuggerAgent::functionExit(), QDeclarativeInclude::include(), QDeclarativeWorkerScriptEnginePrivate::processLoad(), QDeclarativeWorkerScriptEnginePrivate::processMessage(), and QDeclarativeInclude::worker_include().

{
    Q_D(QScriptEngine);
    JSC::ExecState* exec = d->currentFrame;
    exec->clearException();
    d->clearCurrentException();
}

collectGarbage()

void QScriptEngine::collectGarbage

(

)

Runs the garbage collector.

The garbage collector will attempt to reclaim memory by locating and disposing of objects that are no longer reachable in the script environment.

Normally you don't need to call this function; the garbage collector will automatically be invoked when the QScriptEngine decides that it's wise to do so (i.e. when a certain number of new objects have been created). However, you can call this function to explicitly request that garbage collection should be performed as soon as possible.

See also

reportAdditionalMemoryCost()

Definition at line 4097 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    d->collectGarbage();
}

convert()

bool QScriptEngine::convert ( const QScriptValue &  value, int  type, void *  ptr  )

private

Warning

This function is not part of the public interface.

Definition at line 3461 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return QScriptEnginePrivate::convertValue(d->currentFrame, d->scriptValueToJSCValue(value), type, ptr);
}

convertV2()

bool QScriptEngine::convertV2 ( const QScriptValue &  value, int  type, void *  ptr  )

staticprivate

Warning

This function is not part of the public interface.

Definition at line 3471 of file qscriptengine.cpp.

Referenced by qscriptvalue_cast_helper().

{
    QScriptValuePrivate *vp = QScriptValuePrivate::get(value);
    if (vp) {
        switch (vp->type) {
        case QScriptValuePrivate::JavaScriptCore: {
            if (vp->engine) {
                QScript::APIShim shim(vp->engine);
                return QScriptEnginePrivate::convertValue(vp->engine->currentFrame, vp->jscValue, type, ptr);
            } else {
                return QScriptEnginePrivate::convertValue(0, vp->jscValue, type, ptr);
            }
        }
        case QScriptValuePrivate::Number:
            return QScriptEnginePrivate::convertNumber(vp->numberValue, type, ptr);
        case QScriptValuePrivate::String:
            return QScriptEnginePrivate::convertString(vp->stringValue, type, ptr);
        }
    }
    return false;
}

create()

QScriptValue QScriptEngine::create ( int  type, const void *  ptr  )

private

Warning

This function is not part of the public interface.

Definition at line 3049 of file qscriptengine.cpp.

Referenced by QScriptEnginePrivate::create(), and qScriptValueFromValue_helper().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->scriptValueFromJSCValue(d->create(d->currentFrame, type, ptr));
}

currentContext()

QScriptContext * QScriptEngine::currentContext

(

)

const

Returns the current context.

The current context is typically accessed to retrieve the arguments and `this' object in native functions; for convenience, it is available as the first argument in QScriptEngine::FunctionSignature.

Definition at line 2720 of file qscriptengine.cpp.

Referenced by QScriptDebuggerBackend::backtrace(), QScriptDebuggerBackend::context(), QDeclarativeObjectScriptClass::destroy(), QScriptDebuggerAgent::enterReturnByForceMode(), importExtension(), QJSDebuggerAgent::localsAtFrame(), popContext(), QJSDebuggerAgentPrivate::positionChange(), QScriptDebuggerAgent::QScriptDebuggerAgent(), and QDeclarativeGlobalScriptClass::setProperty().

{
    Q_D(const QScriptEngine);
    return const_cast<QScriptEnginePrivate*>(d)->contextForFrame(d->currentFrame);
}

defaultPrototype()

QScriptValue QScriptEngine::defaultPrototype

(

int

metaTypeId

)

const

Returns the default prototype associated with the given metaTypeId, or an invalid QScriptValue if no default prototype has been set.

See also

setDefaultPrototype()

Definition at line 2984 of file qscriptengine.cpp.

{
    Q_D(const QScriptEngine);
    return const_cast<QScriptEnginePrivate*>(d)->scriptValueFromJSCValue(d->defaultPrototype(metaTypeId));
}

evaluate() [1/2]

QScriptValue QScriptEngine::evaluate	(	const QString &	program,
		const QString &	fileName = QString(),
		int	lineNumber = 1
	)

Evaluates program, using lineNumber as the base line number, and returns the result of the evaluation.

The script code will be evaluated in the current context.

The evaluation of program can cause an exception in the engine; in this case the return value will be the exception that was thrown (typically an Error object). You can call hasUncaughtException() to determine if an exception occurred in the last call to evaluate().

lineNumber is used to specify a starting line number for program; line number information reported by the engine that pertain to this evaluation (e.g. uncaughtExceptionLineNumber()) will be based on this argument. For example, if program consists of two lines of code, and the statement on the second line causes a script exception, uncaughtExceptionLineNumber() would return the given lineNumber plus one. When no starting line number is specified, line numbers will be 1-based.

fileName is used for error reporting. For example in error objects the file name is accessible through the "fileName" property if it's provided with this function.

See also

canEvaluate(), hasUncaughtException(), isEvaluating(), abortEvaluation()

Definition at line 2671 of file qscriptengine.cpp.

Referenced by QDeclarativeContextData::addImportedScript(), QScriptDebuggerBackend::doPendingEvaluate(), QDeclarativeExpressionPrivate::evalInObjectScope(), QDeclarativeInclude::finished(), importExtension(), QDeclarativeInclude::include(), QDeclarativeExpressionPrivate::init(), QScriptDebuggerScriptedConsoleCommand::parse(), QScriptDebuggerAgent::positionChange(), QDeclarativeWorkerScriptEnginePrivate::processLoad(), QDeclarativeExpressionPrivate::scriptValue(), QJSDebuggerAgent::setProperty(), and QDeclarativeInclude::worker_include().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    WTF::PassRefPtr<QScript::UStringSourceProviderWithFeedback> provider
            = QScript::UStringSourceProviderWithFeedback::create(program, fileName, lineNumber, d);
    intptr_t sourceId = provider->asID();
    JSC::SourceCode source(provider, lineNumber); //after construction of SourceCode provider variable will be null.

    JSC::ExecState* exec = d->currentFrame;
    WTF::RefPtr<JSC::EvalExecutable> executable = JSC::EvalExecutable::create(exec, source);
    bool compile = true;
    return d->scriptValueFromJSCValue(d->evaluateHelper(exec, sourceId, executable.get(), compile));
}

evaluate() [2/2]

QScriptValue QScriptEngine::evaluate

(

const QScriptProgram &

program

)

Evaluates the given program and returns the result of the evaluation.

Since

4.7

Definition at line 2695 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    QScriptProgramPrivate *program_d = QScriptProgramPrivate::get(program);
    if (!program_d)
        return QScriptValue();

    QScript::APIShim shim(d);
    JSC::ExecState* exec = d->currentFrame;
    JSC::EvalExecutable *executable = program_d->executable(exec, d);
    bool compile = !program_d->isCompiled;
    JSC::JSValue result = d->evaluateHelper(exec, program_d->sourceId,
                                            executable, compile);
    if (compile)
        program_d->isCompiled = true;
    return d->scriptValueFromJSCValue(result);
}

fromScriptValue()

template<typename T >

T QScriptEngine::fromScriptValue ( const QScriptValue &  value )

inline

Returns the given value converted to the template type T.

Note that T must be known to QMetaType.

See Conversion Between QtScript and C++ Types for a description of the built-in type conversion provided by QtScript.

See also

toScriptValue(), qScriptRegisterMetaType()

Definition at line 218 of file qscriptengine.h.

    {
        return qscriptvalue_cast<T>(value);
    }

globalObject()

QScriptValue QScriptEngine::globalObject

(

)

const

Returns this engine's Global Object.

By default, the Global Object contains the built-in objects that are part of ECMA-262, such as Math, Date and String. Additionally, you can set properties of the Global Object to make your own extensions available to all script code. Non-local variables in script code will be created as properties of the Global Object, as well as local variables in global code.

Definition at line 2030 of file qscriptengine.cpp.

Referenced by QScript::__setupPackage__(), QScriptContext::activationObject(), QScriptDebuggerBackend::attachTo(), QScriptDebuggerBackend::detach(), QDeclarativeGlobalScriptClass::explicitSetProperty(), QJSDebuggerAgentPrivate::getLocals(), importExtension(), QtDBusScriptPlugin::initialize(), QScriptDebuggerScriptedConsoleCommand::parse(), QDBusConnectionConstructor::QDBusConnectionConstructor(), QDeclarativeGlobalScriptClass::QDeclarativeGlobalScriptClass(), QDeclarativeScriptEngine::QDeclarativeScriptEngine(), qt_add_qmlsqldatabase(), qt_add_qmlxmlhttprequest(), QScriptExtensionPlugin::setupPackage(), and QScriptDebuggerScriptedConsoleCommandJob::start().

{
    Q_D(const QScriptEngine);
    QScript::APIShim shim(const_cast<QScriptEnginePrivate*>(d));
    JSC::JSObject *result = d->globalObject();
    return const_cast<QScriptEnginePrivate*>(d)->scriptValueFromJSCValue(result);
}

hasUncaughtException()

bool QScriptEngine::hasUncaughtException

(

)

const

Returns true if the last script evaluation resulted in an uncaught exception; otherwise returns false.

The exception state is cleared when evaluate() is called.

See also

uncaughtException(), uncaughtExceptionLineNumber()

Definition at line 2893 of file qscriptengine.cpp.

Referenced by QDeclarativeContextData::addImportedScript(), QScriptDebuggerBackend::doPendingEvaluate(), QDeclarativeQtScriptExpression::eval(), QDeclarativeExpressionPrivate::exceptionToError(), QScriptDebuggerCommandExecutor::execute(), QDeclarativeInclude::finished(), importExtension(), QDeclarativeInclude::include(), QScriptDebuggerScriptedConsoleCommand::parse(), QDeclarativeWorkerScriptEnginePrivate::processLoad(), QDeclarativeWorkerScriptEnginePrivate::processMessage(), qmlsqldatabase_change_version(), qmlsqldatabase_transaction_shared(), QDeclarativeWorkerScriptEnginePrivate::reportScriptException(), uncaughtExceptionBacktrace(), uncaughtExceptionLineNumber(), and QDeclarativeInclude::worker_include().

{
    Q_D(const QScriptEngine);
    JSC::ExecState* exec = d->globalExec();
    return exec->hadException() || d->currentException().isValid();
}

importedExtensions()

QStringList QScriptEngine::importedExtensions

(

)

const

Returns a list naming the extensions that have been imported using the importExtension() function.

Since

4.4

See also

availableExtensions()

Definition at line 3831 of file qscriptengine.cpp.

{
    Q_D(const QScriptEngine);
    QStringList lst = d->importedExtensions.toList();
    qSort(lst);
    return lst;
}

importExtension()

QScriptValue QScriptEngine::importExtension

(

const QString &

extension

)

Imports the given extension into this QScriptEngine.

Returns undefinedValue() if the extension was successfully imported. You can call hasUncaughtException() to check if an error occurred; in that case, the return value is the value that was thrown by the exception (usually an Error object).

QScriptEngine ensures that a particular extension is only imported once; subsequent calls to importExtension() with the same extension name will do nothing and return undefinedValue().

See also

availableExtensions(), QScriptExtensionPlugin, {Creating QtScript Extensions}

Definition at line 3572 of file qscriptengine.cpp.

{
#if defined(QT_NO_QOBJECT) || defined(QT_NO_LIBRARY) || defined(QT_NO_SETTINGS)
    Q_UNUSED(extension);
#else
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    if (d->importedExtensions.contains(extension))
        return undefinedValue(); // already imported

    QScriptContext *context = currentContext();
    QCoreApplication *app = QCoreApplication::instance();
    if (!app)
        return context->throwError(QLatin1String("No application object"));

    QObjectList staticPlugins = QPluginLoader::staticInstances();
    QStringList libraryPaths = app->libraryPaths();
    QString dot = QLatin1String(".");
    QStringList pathComponents = extension.split(dot);
    QString initDotJs = QLatin1String("__init__.js");

    QString ext;
    for (int i = 0; i < pathComponents.count(); ++i) {
        if (!ext.isEmpty())
            ext.append(dot);
        ext.append(pathComponents.at(i));
        if (d->importedExtensions.contains(ext))
            continue; // already imported

        if (d->extensionsBeingImported.contains(ext)) {
            return context->throwError(QString::fromLatin1("recursive import of %0")
                                       .arg(extension));
        }
        d->extensionsBeingImported.insert(ext);

        QScriptExtensionInterface *iface = 0;
        QString initjsContents;
        QString initjsFileName;

        // look for the extension in static plugins
        for (int j = 0; j < staticPlugins.size(); ++j) {
            iface = qobject_cast<QScriptExtensionInterface*>(staticPlugins.at(j));
            if (!iface)
                continue;
            if (iface->keys().contains(ext))
                break; // use this one
            else
                iface = 0; // keep looking
        }

        {
            // look for __init__.js resource
            QString path = QString::fromLatin1(":/qtscriptextension");
            for (int j = 0; j <= i; ++j) {
                path.append(QLatin1Char('/'));
                path.append(pathComponents.at(j));
            }
            path.append(QLatin1Char('/'));
            path.append(initDotJs);
            QFile file(path);
            if (file.open(QIODevice::ReadOnly)) {
                QTextStream ts(&file);
                initjsContents = ts.readAll();
                initjsFileName = path;
                file.close();
            }
        }

        if (!iface && initjsContents.isEmpty()) {
            // look for the extension in library paths
            for (int j = 0; j < libraryPaths.count(); ++j) {
                QString libPath = libraryPaths.at(j) + QDir::separator() + QLatin1String("script");
                QDir dir(libPath);
                if (!dir.exists(dot))
                    continue;

                // look for C++ plugin
                QFileInfoList files = dir.entryInfoList(QDir::Files);
                for (int k = 0; k < files.count(); ++k) {
                    QFileInfo entry = files.at(k);
                    QString filePath = entry.canonicalFilePath();
                    QPluginLoader loader(filePath);
                    iface = qobject_cast<QScriptExtensionInterface*>(loader.instance());
                    if (iface) {
                        if (iface->keys().contains(ext))
                            break; // use this one
                        else
                            iface = 0; // keep looking
                    }
                }

                // look for __init__.js in the corresponding dir
                QDir dirdir(libPath);
                bool dirExists = dirdir.exists();
                for (int k = 0; dirExists && (k <= i); ++k)
                    dirExists = dirdir.cd(pathComponents.at(k));
                if (dirExists && dirdir.exists(initDotJs)) {
                    QFile file(dirdir.canonicalPath()
                               + QDir::separator() + initDotJs);
                    if (file.open(QIODevice::ReadOnly)) {
                        QTextStream ts(&file);
                        initjsContents = ts.readAll();
                        initjsFileName = file.fileName();
                        file.close();
                    }
                }

                if (iface || !initjsContents.isEmpty())
                    break;
            }
        }

        if (!iface && initjsContents.isEmpty()) {
            d->extensionsBeingImported.remove(ext);
            return context->throwError(
                QString::fromLatin1("Unable to import %0: no such extension")
                .arg(extension));
        }

        // initialize the extension in a new context
        QScriptContext *ctx = pushContext();
        ctx->setThisObject(globalObject());
        ctx->activationObject().setProperty(QLatin1String("__extension__"), ext,
                                            QScriptValue::ReadOnly | QScriptValue::Undeletable);
        ctx->activationObject().setProperty(QLatin1String("__setupPackage__"),
                                            newFunction(QScript::__setupPackage__));
        ctx->activationObject().setProperty(QLatin1String("__postInit__"), QScriptValue(QScriptValue::UndefinedValue));

        // the script is evaluated first
        if (!initjsContents.isEmpty()) {
            QScriptValue ret = evaluate(initjsContents, initjsFileName);
            if (hasUncaughtException()) {
                popContext();
                d->extensionsBeingImported.remove(ext);
                return ret;
            }
        }

        // next, the C++ plugin is called
        if (iface) {
            iface->initialize(ext, this);
            if (hasUncaughtException()) {
                QScriptValue ret = uncaughtException(); // ctx_p->returnValue();
                popContext();
                d->extensionsBeingImported.remove(ext);
                return ret;
            }
        }

        // if the __postInit__ function has been set, we call it
        QScriptValue postInit = ctx->activationObject().property(QLatin1String("__postInit__"));
        if (postInit.isFunction()) {
            postInit.call(globalObject());
            if (hasUncaughtException()) {
                QScriptValue ret = uncaughtException(); // ctx_p->returnValue();
                popContext();
                d->extensionsBeingImported.remove(ext);
                return ret;
            }
        }

        popContext();

        d->importedExtensions.insert(ext);
        d->extensionsBeingImported.remove(ext);
    } // for (i)
#endif // QT_NO_QOBJECT
    return undefinedValue();
}

installTranslatorFunctions()

void QScriptEngine::installTranslatorFunctions

(

const QScriptValue &

object = QScriptValue()

)

Installs translator functions on the given object, or on the Global Object if no object is specified.

Since

4.5

The relation between Qt Script translator functions and C++ translator functions is described in the following table:

Script Function	Corresponding C++ Function
qsTr()	QObject::tr()
QT_TR_NOOP()	QT_TR_NOOP()
qsTranslate()	QCoreApplication::translate()
QT_TRANSLATE_NOOP()	QT_TRANSLATE_NOOP()
qsTrId() (since 4.7)	qtTrId()
QT_TRID_NOOP() (since 4.7)	QT_TRID_NOOP()

See also

{Internationalization with Qt}

Definition at line 3536 of file qscriptengine.cpp.

Referenced by QDeclarativeScriptEngine::QDeclarativeScriptEngine().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::ExecState* exec = d->currentFrame;
    JSC::JSValue jscObject = d->scriptValueToJSCValue(object);
    JSC::JSGlobalObject *glob = d->originalGlobalObject();
    if (!jscObject || !jscObject.isObject())
        jscObject = d->globalObject();
//    unsigned attribs = JSC::DontEnum;

#ifndef QT_NO_TRANSLATION
    JSC::asObject(jscObject)->putDirectFunction(exec, new (exec)JSC::NativeFunctionWrapper(exec, glob->prototypeFunctionStructure(), 5, JSC::Identifier(exec, "qsTranslate"), QScript::functionQsTranslate));
    JSC::asObject(jscObject)->putDirectFunction(exec, new (exec)JSC::NativeFunctionWrapper(exec, glob->prototypeFunctionStructure(), 2, JSC::Identifier(exec, "QT_TRANSLATE_NOOP"), QScript::functionQsTranslateNoOp));
    JSC::asObject(jscObject)->putDirectFunction(exec, new (exec)JSC::NativeFunctionWrapper(exec, glob->prototypeFunctionStructure(), 3, JSC::Identifier(exec, "qsTr"), QScript::functionQsTr));
    JSC::asObject(jscObject)->putDirectFunction(exec, new (exec)JSC::NativeFunctionWrapper(exec, glob->prototypeFunctionStructure(), 1, JSC::Identifier(exec, "QT_TR_NOOP"), QScript::functionQsTrNoOp));
    JSC::asObject(jscObject)->putDirectFunction(exec, new (exec)JSC::NativeFunctionWrapper(exec, glob->prototypeFunctionStructure(), 1, JSC::Identifier(exec, "qsTrId"), QScript::functionQsTrId));
    JSC::asObject(jscObject)->putDirectFunction(exec, new (exec)JSC::NativeFunctionWrapper(exec, glob->prototypeFunctionStructure(), 1, JSC::Identifier(exec, "QT_TRID_NOOP"), QScript::functionQsTrIdNoOp));
#endif

    glob->stringPrototype()->putDirectFunction(exec, new (exec)JSC::NativeFunctionWrapper(exec, glob->prototypeFunctionStructure(), 1, JSC::Identifier(exec, "arg"), QScript::stringProtoFuncArg));
}

isEvaluating()

bool QScriptEngine::isEvaluating

(

)

const

Returns true if this engine is currently evaluating a script, otherwise returns false.

Since

4.4

See also

evaluate(), abortEvaluation()

Definition at line 4191 of file qscriptengine.cpp.

Referenced by abortEvaluation(), and QScriptDebuggerCommandExecutor::execute().

{
    Q_D(const QScriptEngine);
    return (d->currentFrame != d->globalExec()) || d->inEval;
}

newActivationObject()

QScriptValue QScriptEngine::newActivationObject

(

)

Warning

This function is not part of the public interface.

Definition at line 2339 of file qscriptengine.cpp.

{
    qWarning("QScriptEngine::newActivationObject() not implemented");
    // ### JSActivation or JSVariableObject?
    return QScriptValue();
}

newArray()

QScriptValue QScriptEngine::newArray

(

uint

length = 0

)

Creates a QtScript object of class Array with the given length.

See also

newObject()

Definition at line 2426 of file qscriptengine.cpp.

Referenced by QDeclarativeInclude::callback(), QDeclarativeEnginePrivate::createQmlObject(), messageToScriptValue(), QDeclarativeWorkerScriptEnginePrivate::processMessage(), QDeclarativeObjectMethodScriptClass::property(), qDBusReplyToScriptValue(), qScriptValueFromSequence(), and QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->scriptValueFromJSCValue(d->newArray(d->currentFrame, length));
}

newDate() [1/2]

QScriptValue QScriptEngine::newDate

(

qsreal

value

)

Creates a QtScript object of class Date with the given value (the number of milliseconds since 01 January 1970, UTC).

Definition at line 2452 of file qscriptengine.cpp.

Referenced by QScriptEnginePrivate::create(), and QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->scriptValueFromJSCValue(d->newDate(d->currentFrame, value));
}

newDate() [2/2]

QScriptValue QScriptEngine::newDate

(

const QDateTime &

value

)

Creates a QtScript object of class Date from the given value.

See also

QScriptValue::toDateTime()

Definition at line 2464 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->scriptValueFromJSCValue(d->newDate(d->currentFrame, value));
}

newFunction() [1/3]

QScriptValue QScriptEngine::newFunction	(	QScriptEngine::FunctionSignature	fun,
		int	length = 0
	)

Creates a QScriptValue that wraps a native (C++) function.

fun must be a C++ function with signature QScriptEngine::FunctionSignature. length is the number of arguments that fun expects; this becomes the length property of the created QScriptValue.

Note that length only gives an indication of the number of arguments that the function expects; an actual invocation of a function can include any number of arguments. You can check the argumentCount() of the QScriptContext associated with the invocation to determine the actual number of arguments passed.

A prototype property is automatically created for the resulting function object, to provide for the possibility that the function will be used as a constructor.

By combining newFunction() and the property flags QScriptValue::PropertyGetter and QScriptValue::PropertySetter, you can create script object properties that behave like normal properties in script code, but are in fact accessed through functions (analogous to how properties work in Qt's Property System). Example:

static QScriptValue getSetFoo(QScriptContext *context, QScriptEngine *engine)
{
    QScriptValue callee = context->callee();
    if (context->argumentCount() == 1) // writing?
        callee.setProperty("value", context->argument(0));
    return callee.property("value");
}

....

QScriptValue object = engine.newObject();
object.setProperty("foo", engine.newFunction(getSetFoo),
    QScriptValue::PropertyGetter | QScriptValue::PropertySetter);

When the property foo of the script object is subsequently accessed in script code, getSetFoo() will be invoked to handle the access. In this particular case, we chose to store the "real" value of foo as a property of the accessor function itself; you are of course free to do whatever you like in this function.

In the above example, a single native function was used to handle both reads and writes to the property; the argument count is used to determine if we are handling a read or write. You can also use two separate functions; just specify the relevant flag (QScriptValue::PropertyGetter or QScriptValue::PropertySetter) when setting the property, e.g.:

QScriptValue object = engine.newObject();
object.setProperty("foo", engine.newFunction(getFoo), QScriptValue::PropertyGetter);
object.setProperty("foo", engine.newFunction(setFoo), QScriptValue::PropertySetter);

See also

QScriptValue::call()

Definition at line 2389 of file qscriptengine.cpp.

Referenced by QScriptDebuggerBackend::assertFunction(), QScriptDebuggerBackend::fileNameFunction(), QDeclarativeWorkerScriptEnginePrivate::getWorker(), importExtension(), QScriptDebuggerBackend::lineNumberFunction(), NamedNodeMap::prototype(), NodeList::prototype(), Node::prototype(), Element::prototype(), Attr::prototype(), CharacterData::prototype(), Text::prototype(), Document::prototype(), QDeclarativeObjectMethodScriptClass::QDeclarativeObjectMethodScriptClass(), QDeclarativeObjectScriptClass::QDeclarativeObjectScriptClass(), QDeclarativeScriptEngine::QDeclarativeScriptEngine(), qmlsqldatabase_change_version(), qmlsqldatabase_executeSql(), qmlsqldatabase_open_sync(), qmlsqldatabase_transaction_shared(), QScriptDBusMessageConstructor::QScriptDBusMessageConstructor(), qt_add_qmlsqldatabase(), qt_add_qmlxmlhttprequest(), setupDBusInterface(), and QScriptDebuggerBackend::traceFunction().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::ExecState* exec = d->currentFrame;
    JSC::JSValue function = new (exec)QScript::FunctionWrapper(exec, length, JSC::Identifier(exec, ""), fun);
    QScriptValue result = d->scriptValueFromJSCValue(function);
    QScriptValue proto = newObject();
    result.setProperty(QLatin1String("prototype"), proto,
                       QScriptValue::Undeletable | QScriptValue::SkipInEnumeration);
    proto.setProperty(QLatin1String("constructor"), result, QScriptValue::SkipInEnumeration);
    return result;
}

newFunction() [2/3]

QScriptValue QScriptEngine::newFunction	(	QScriptEngine::FunctionSignature	fun,
		const QScriptValue &	prototype,
		int	length = 0
	)

Creates a constructor function from fun, with the given length.

The prototype property of the resulting function is set to be the given prototype. The constructor property of prototype is set to be the resulting function.

When a function is called as a constructor (e.g. new Foo()), the `this' object associated with the function call is the new object that the function is expected to initialize; the prototype of this default constructed object will be the function's public prototype property. If you always want the function to behave as a constructor (e.g. Foo() should also create a new object), or if you need to create your own object rather than using the default `this' object, you should make sure that the prototype of your object is set correctly; either by setting it manually, or, when wrapping a custom type, by having registered the defaultPrototype() of that type. Example:

QScriptValue Foo(QScriptContext *context, QScriptEngine *engine)
{
    if (context->calledAsConstructor()) {
        // initialize the new object
        context->thisObject().setProperty("bar", ...);
        // ...
        // return a non-object value to indicate that the
        // thisObject() should be the result of the "new Foo()" expression
        return engine->undefinedValue();
    } else {
        // not called as "new Foo()", just "Foo()"
        // create our own object and return that one
        QScriptValue object = engine->newObject();
        object.setPrototype(context->callee().property("prototype"));
        object.setProperty("baz", ...);
        return object;
    }
}

...

QScriptValue fooProto = engine->newObject();
fooProto.setProperty("whatever", ...);
engine->globalObject().setProperty("Foo", engine->newFunction(Foo, fooProto));

To wrap a custom type and provide a constructor for it, you'd typically do something like this:

class Bar { ... };

Q_DECLARE_METATYPE(Bar)

QScriptValue constructBar(QScriptContext *context, QScriptEngine *engine)
{
    Bar bar;
    // initialize from arguments in context, if desired
    ...
    return engine->toScriptValue(bar);
}

class BarPrototype : public QObject, public QScriptable
{
// provide the scriptable interface of this type using slots and properties
...
};

...

// create and register the Bar prototype and constructor in the engine
BarPrototype *barPrototypeObject = new BarPrototype(...);
QScriptValue barProto = engine->newQObject(barPrototypeObject);
engine->setDefaultPrototype(qMetaTypeId<Bar>, barProto);
QScriptValue barCtor = engine->newFunction(constructBar, barProto);
engine->globalObject().setProperty("Bar", barCtor);

Definition at line 2110 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::ExecState* exec = d->currentFrame;
    JSC::JSValue function = new (exec)QScript::FunctionWrapper(exec, length, JSC::Identifier(exec, ""), fun);
    QScriptValue result = d->scriptValueFromJSCValue(function);
    result.setProperty(QLatin1String("prototype"), prototype,
                       QScriptValue::Undeletable | QScriptValue::SkipInEnumeration);
    const_cast<QScriptValue&>(prototype)
        .setProperty(QLatin1String("constructor"), result, QScriptValue::SkipInEnumeration);
    return result;
}

newFunction() [3/3]

QScriptValue QScriptEngine::newFunction	(	QScriptEngine::FunctionWithArgSignature	fun,
		void *	arg
	)

Warning

This function is not part of the public interface.

Since

4.4

Definition at line 2407 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::ExecState* exec = d->currentFrame;
    JSC::JSValue function = new (exec)QScript::FunctionWithArgWrapper(exec, /*length=*/0, JSC::Identifier(exec, ""), fun, arg);
    QScriptValue result = d->scriptValueFromJSCValue(function);
    QScriptValue proto = newObject();
    result.setProperty(QLatin1String("prototype"), proto,
                       QScriptValue::Undeletable | QScriptValue::SkipInEnumeration);
    proto.setProperty(QLatin1String("constructor"), result, QScriptValue::SkipInEnumeration);
    return result;
}

newObject() [1/2]

QScriptValue QScriptEngine::newObject

(

)

Creates a QtScript object of class Object.

The prototype of the created object will be the Object prototype object.

See also

newArray(), QScriptValue::setProperty()

Definition at line 2296 of file qscriptengine.cpp.

Referenced by QScript::__setupPackage__(), breakpointDataToScriptValue(), breakpointMapToScriptValue(), consoleCommandGroupDataToScriptValue(), consoleCommandGroupMapToScriptValue(), consoleCommandToScriptValue(), contextInfoToScriptValue(), NamedNodeMap::create(), NodeList::create(), Node::create(), QDeclarativeEnginePrivate::createQmlObject(), debuggerResponseToScriptValue(), debuggerScriptValuePropertyToScriptValue(), QDeclarativeGlobalScriptClass::explicitSetProperty(), QDeclarativeXmlListModel::get(), QDeclarativeWorkerScriptEnginePrivate::getWorker(), Document::load(), QDeclarativeItem::mapFromItem(), QDeclarativeItem::mapToItem(), newFunction(), QDeclarativeWorkerScriptEnginePrivate::processLoad(), ModelNodeMetaObject::propertyWritten(), NamedNodeMap::prototype(), NodeList::prototype(), Node::prototype(), Element::prototype(), Attr::prototype(), CharacterData::prototype(), Text::prototype(), CDATA::prototype(), Document::prototype(), qDBusErrorToScriptValue(), QDeclarativeGlobalScriptClass::QDeclarativeGlobalScriptClass(), QDeclarativeScriptEngine::QDeclarativeScriptEngine(), qmlsqldatabase_change_version(), qmlsqldatabase_executeSql(), qmlsqldatabase_item(), qmlsqldatabase_open_sync(), qmlsqldatabase_transaction_shared(), qt_add_qmlsqldatabase(), qt_add_qmlxmlhttprequest(), QDeclarativeInclude::resultValue(), scriptDataToScriptValue(), scriptMapToScriptValue(), QScriptExtensionPlugin::setupPackage(), QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue(), and QDeclarativeInclude::worker_include().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->scriptValueFromJSCValue(d->newObject());
}

newObject() [2/2]

QScriptValue QScriptEngine::newObject	(	QScriptClass *	scriptClass,
		const QScriptValue &	data = QScriptValue()
	)

Creates a QtScript Object of the given class, scriptClass.

Since

4.4 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

The prototype of the created object will be the Object prototype object.

data, if specified, is set as the internal data of the new object (using QScriptValue::setData()).

See also

QScriptValue::scriptClass(), reportAdditionalMemoryCost()

Definition at line 2320 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::ExecState* exec = d->currentFrame;
    QScriptObject *result = new (exec) QScriptObject(d->scriptObjectStructure);
    result->setDelegate(new QScript::ClassObjectDelegate(scriptClass));
    QScriptValue scriptObject = d->scriptValueFromJSCValue(result);
    scriptObject.setData(data);
    QScriptValue proto = scriptClass->prototype();
    if (proto.isValid())
        scriptObject.setPrototype(proto);
    return scriptObject;
}

newQMetaObject()

QScriptValue QScriptEngine::newQMetaObject	(	const QMetaObject *	metaObject,
		const QScriptValue &	ctor = QScriptValue()
	)

Creates a QtScript object that represents a QObject class, using the the given metaObject and constructor ctor.

Enums of metaObject (declared with Q_ENUMS) are available as properties of the created QScriptValue. When the class is called as a function, ctor will be called to create a new instance of the class.

Example:

QScriptValue mySpecialQObjectConstructor(QScriptContext *context,
                                         QScriptEngine *engine)
{
    QObject *parent = context->argument(0).toQObject();
    QObject *object = new QObject(parent);
    return engine->newQObject(object, QScriptEngine::ScriptOwnership);
}

...

QScriptValue ctor = engine.newFunction(mySpecialQObjectConstructor);
QScriptValue metaObject = engine.newQMetaObject(&QObject::staticMetaObject, ctor);
engine.globalObject().setProperty("QObject", metaObject);

QScriptValue result = engine.evaluate("new QObject()");

See also

newQObject(), scriptValueFromQMetaObject()

Definition at line 2487 of file qscriptengine.cpp.

Referenced by QDBusConnectionConstructor::QDBusConnectionConstructor(), QDeclarativeScriptEngine::QDeclarativeScriptEngine(), QScriptDBusInterfaceConstructor::QScriptDBusInterfaceConstructor(), and QScriptDBusMessageConstructor::QScriptDBusMessageConstructor().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::JSValue jscCtor = d->scriptValueToJSCValue(ctor);
    JSC::JSValue jscQMetaObject = d->newQMetaObject(metaObject, jscCtor);
    return d->scriptValueFromJSCValue(jscQMetaObject);
}

newQObject() [1/2]

QScriptValue QScriptEngine::newQObject	(	QObject *	object,
		ValueOwnership	ownership = QtOwnership,
		const QObjectWrapOptions &	options = 0
	)

Creates a QtScript object that wraps the given QObject object, using the given ownership.

The given options control various aspects of the interaction with the resulting script object.

Signals and slots, properties and children of object are available as properties of the created QScriptValue. For more information, see the QtScript documentation.

If object is a null pointer, this function returns nullValue().

If a default prototype has been registered for the object's class (or its superclass, recursively), the prototype of the new script object will be set to be that default prototype.

If the given object is deleted outside of QtScript's control, any attempt to access the deleted QObject's members through the QtScript wrapper object (either by script code or C++) will result in a script exception.

See also

QScriptValue::toQObject(), reportAdditionalMemoryCost()

Definition at line 2221 of file qscriptengine.cpp.

Referenced by newQObject(), QScriptDebuggerScriptedConsoleCommand::parse(), QDBusConnectionConstructor::QDBusConnectionConstructor(), qmlxmlhttprequest_new(), QScriptDBusInterfaceConstructor::QScriptDBusInterfaceConstructor(), QScriptDBusMessageConstructor::QScriptDBusMessageConstructor(), setupDBusInterface(), and QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::JSValue jscQObject = d->newQObject(object, ownership, options);
    return d->scriptValueFromJSCValue(jscQObject);
}

newQObject() [2/2]

QScriptValue QScriptEngine::newQObject	(	const QScriptValue &	scriptObject,
		QObject *	qtObject,
		ValueOwnership	ownership = QtOwnership,
		const QObjectWrapOptions &	options = 0
	)

Initializes the given scriptObject to hold the given qtObject, and returns the scriptObject.

Since

4.4 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

This function enables you to "promote" a plain Qt Script object (created by the newObject() function) to a QObject proxy, or to replace the QObject contained inside an object previously created by the newQObject() function.

The prototype() of the scriptObject will remain unchanged.

If scriptObject is not an object, this function behaves like the normal newQObject(), i.e. it creates a new script object and returns it.

This function is useful when you want to provide a script constructor for a QObject-based class. If your constructor is invoked in a new expression (QScriptContext::isCalledAsConstructor() returns true), you can pass QScriptContext::thisObject() (the default constructed script object) to this function to initialize the new object.

See also

reportAdditionalMemoryCost()

Definition at line 2260 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    if (!scriptObject.isObject())
        return newQObject(qtObject, ownership, options);
    QScript::APIShim shim(d);
    JSC::JSObject *jscObject = JSC::asObject(QScriptValuePrivate::get(scriptObject)->jscValue);
    if (!jscObject->inherits(&QScriptObject::info)) {
        qWarning("QScriptEngine::newQObject(): changing class of non-QScriptObject not supported");
        return QScriptValue();
    }
    QScriptObject *jscScriptObject = static_cast<QScriptObject*>(jscObject);
    if (!scriptObject.isQObject()) {
        jscScriptObject->setDelegate(new QScript::QObjectDelegate(qtObject, ownership, options));
    } else {
        QScript::QObjectDelegate *delegate = static_cast<QScript::QObjectDelegate*>(jscScriptObject->delegate());
        delegate->setValue(qtObject);
        delegate->setOwnership(ownership);
        delegate->setOptions(options);
    }
    return scriptObject;
}

newRegExp() [1/2]

QScriptValue QScriptEngine::newRegExp

(

const QRegExp &

regexp

)

Creates a QtScript object of class RegExp with the given regexp.

See also

QScriptValue::toRegExp()

Definition at line 2134 of file qscriptengine.cpp.

Referenced by QScriptEnginePrivate::create(), and QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->scriptValueFromJSCValue(d->newRegExp(d->currentFrame, regexp));
}

newRegExp() [2/2]

QScriptValue QScriptEngine::newRegExp	(	const QString &	pattern,
		const QString &	flags
	)

Creates a QtScript object of class RegExp with the given pattern and flags.

The legal flags are 'g' (global), 'i' (ignore case), and 'm' (multiline).

Definition at line 2440 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->scriptValueFromJSCValue(d->newRegExp(d->currentFrame, pattern, flags));
}

newVariant() [1/2]

QScriptValue QScriptEngine::newVariant

(

const QVariant &

value

)

Creates a QtScript object holding the given variant value.

If a default prototype has been registered with the meta type id of value, then the prototype of the created object will be that prototype; otherwise, the prototype will be the Object prototype object.

See also

setDefaultPrototype(), QScriptValue::toVariant(), reportAdditionalMemoryCost()

Definition at line 2153 of file qscriptengine.cpp.

Referenced by QDeclarativeEnginePrivate::consoleLog(), NamedNodeMap::create(), NodeList::create(), Node::create(), do_dbus_call(), QDeclarativeEnginePrivate::formatDate(), QDeclarativeEnginePrivate::formatDateTime(), QDeclarativeEnginePrivate::formatTime(), Document::load(), messageToScriptValue(), ModelNodeMetaObject::propertyWritten(), qmlsqldatabase_change_version(), qmlsqldatabase_executeSql(), qmlsqldatabase_open_sync(), qmlsqldatabase_transaction_shared(), and QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->scriptValueFromJSCValue(d->newVariant(value));
}

newVariant() [2/2]

QScriptValue QScriptEngine::newVariant	(	const QScriptValue &	object,
		const QVariant &	value
	)

Initializes the given Qt Script object to hold the given variant value, and returns the object.

Since

4.4 This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

This function enables you to "promote" a plain Qt Script object (created by the newObject() function) to a variant, or to replace the variant contained inside an object previously created by the newVariant() function.

The prototype() of the object will remain unchanged.

If object is not an object, this function behaves like the normal newVariant(), i.e. it creates a new script object and returns it.

This function is useful when you want to provide a script constructor for a C++ type. If your constructor is invoked in a new expression (QScriptContext::isCalledAsConstructor() returns true), you can pass QScriptContext::thisObject() (the default constructed script object) to this function to initialize the new object.

See also

reportAdditionalMemoryCost()

Definition at line 2189 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::JSValue jsObject = d->scriptValueToJSCValue(object);
    return d->scriptValueFromJSCValue(d->newVariant(jsObject, value));
}

nullValue()

QScriptValue QScriptEngine::nullValue

(

)

Returns a QScriptValue of the primitive type Null.

See also

undefinedValue()

Definition at line 2068 of file qscriptengine.cpp.

Referenced by Node::attributes(), QDeclarativeEnginePrivate::createComponent(), QScriptDBusMessageConstructor::createErrorReply(), QDeclarativeEnginePrivate::createQmlObject(), QDeclarativeEnginePrivate::darker(), do_dbus_call(), Node::firstChild(), QDeclarativeWorkerScriptEnginePrivate::getWorker(), Node::lastChild(), QDeclarativeEnginePrivate::lighter(), Document::load(), QDeclarativeListScriptClass::newList(), QDeclarativeObjectScriptClass::newQObject(), Node::nextSibling(), Node::nodeValue(), Node::parentNode(), Node::previousSibling(), QDeclarativeObjectScriptClass::property(), qmlxmlhttprequest_responseXML(), QScriptDBusConnection::QScriptDBusConnection(), QDeclarativeEnginePrivate::tint(), QScriptDebuggerValue::toScriptValue(), and QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue().

{
    Q_D(QScriptEngine);
    return d->scriptValueFromJSCValue(JSC::jsNull());
}

objectById()

QScriptValue QScriptEngine::objectById

(

qint64

id

)

const

Returns the object with the given id, or an invalid QScriptValue if there is no object with that id.

Warning

This function is not part of the public interface.

See also

QScriptValue::objectId()

Definition at line 4424 of file qscriptengine.cpp.

Referenced by QJSDebuggerAgent::expandObjectById(), QJSDebuggerAgent::setProperty(), and QScriptDebuggerValue::toScriptValue().

{
    Q_D(const QScriptEngine);
    // Assumes that the cell was not been garbage collected
    return const_cast<QScriptEnginePrivate*>(d)->scriptValueFromJSCValue((JSC::JSCell*)id);
}

popContext()

void QScriptEngine::popContext

(

)

Pops the current execution context and restores the previous one.

This function must be used in conjunction with pushContext().

See also

pushContext()

Definition at line 2850 of file qscriptengine.cpp.

Referenced by QDeclarativeContextData::addImportedScript(), QScriptDebuggerBackend::doPendingEvaluate(), QDeclarativeExpressionPrivate::evalInObjectScope(), QDeclarativeInclude::finished(), importExtension(), QDeclarativeInclude::include(), QDeclarativeExpressionPrivate::init(), QDeclarativeWorkerScriptEnginePrivate::processLoad(), QDeclarativeExpressionPrivate::scriptValue(), and QDeclarativeInclude::worker_include().

{
    if (agent())
        agent()->contextPop();
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    if (d->currentFrame->returnPC() != 0 || d->currentFrame->codeBlock() != 0
        || !currentContext()->parentContext()) {
        qWarning("QScriptEngine::popContext() doesn't match with pushContext()");
        return;
    }

    d->popContext();
}

processEventsInterval()

int QScriptEngine::processEventsInterval

(

)

const

Returns the interval in milliseconds between calls to QCoreApplication::processEvents() while the interpreter is running.

See also

setProcessEventsInterval()

Definition at line 4174 of file qscriptengine.cpp.

{
    Q_D(const QScriptEngine);
    return d->processEventsInterval;
}

pushContext()

QScriptContext * QScriptEngine::pushContext

(

)

Enters a new execution context and returns the associated QScriptContext object.

Once you are done with the context, you should call popContext() to restore the old context.

By default, the `this' object of the new context is the Global Object. The context's callee() will be invalid.

This function is useful when you want to evaluate script code as if it were the body of a function. You can use the context's activationObject() to initialize local variables that will be available to scripts. Example:

QScriptEngine engine;
QScriptContext *context = engine.pushContext();
context->activationObject().setProperty("myArg", 123);
engine.evaluate("var tmp = myArg + 42");
...
engine.popContext();

In the above example, the new variable "tmp" defined in the script will be local to the context; in other words, the script doesn't have any effect on the global environment.

Returns 0 in case of stack overflow

See also

popContext()

Definition at line 2751 of file qscriptengine.cpp.

Referenced by QScriptDebuggerBackend::doPendingEvaluate(), and importExtension().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);

    JSC::CallFrame* newFrame = d->pushContext(d->currentFrame, d->currentFrame->globalData().dynamicGlobalObject,
                                              JSC::ArgList(), /*callee = */0);

    if (agent())
        agent()->contextPush();

    return d->contextForFrame(newFrame);
}

registerCustomType()

void QScriptEngine::registerCustomType ( int  type, MarshalFunction  mf, DemarshalFunction  df, const QScriptValue &  prototype  )

private

Warning

This function is not part of the public interface.

Definition at line 3496 of file qscriptengine.cpp.

Referenced by qScriptRegisterMetaType_helper().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    QScriptTypeInfo *info = d->m_typeInfos.value(type);
    if (!info) {
        info = new QScriptTypeInfo();
        d->m_typeInfos.insert(type, info);
    }
    info->marshal = mf;
    info->demarshal = df;
    info->prototype = d->scriptValueToJSCValue(prototype);
}

reportAdditionalMemoryCost()

void QScriptEngine::reportAdditionalMemoryCost

(

int

size

)

Reports an additional memory cost of the given size, measured in bytes, to the garbage collector.

Since

4.7

This function can be called to indicate that a Qt Script object has memory associated with it that isn't managed by Qt Script itself. Reporting the additional cost makes it more likely that the garbage collector will be triggered.

Note that if the additional memory is shared with objects outside the scripting environment, the cost should not be reported, since collecting the Qt Script object would not cause the memory to be freed anyway.

Negative size values are ignored, i.e. this function can't be used to report that the additional memory has been deallocated.

See also

collectGarbage()

Definition at line 4127 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    d->reportAdditionalMemoryCost(size);
}

scriptValueFromQMetaObject()

template<class T >

QScriptValue QScriptEngine::scriptValueFromQMetaObject

(

)

Creates a QScriptValue that represents the Qt class T.

This function is used in combination with one of the Q_SCRIPT_DECLARE_QMETAOBJECT() macro. Example:

Q_SCRIPT_DECLARE_QMETAOBJECT(QLineEdit, QWidget*)

...

QScriptValue lineEditClass = engine.scriptValueFromQMetaObject<QLineEdit>();
engine.globalObject().setProperty("QLineEdit", lineEditClass);

See also

QScriptEngine::newQMetaObject()

Definition at line 295 of file qscriptengine.h.

{
    typedef QScriptValue(*ConstructPtr)(QScriptContext *, QScriptEngine *, T *);
    ConstructPtr cptr = qscriptQMetaObjectConstructor<T>;
    return newQMetaObject(&T::staticMetaObject,
                            newFunction(reinterpret_cast<FunctionWithArgSignature>(cptr), 0));
}

setAgent()

void QScriptEngine::setAgent

(

QScriptEngineAgent *

agent

)

Installs the given agent on this engine.

Since

4.4

The agent will be notified of various events pertaining to script execution. This is useful when you want to find out exactly what the engine is doing, e.g. when evaluate() is called. The agent interface is the basis of tools like debuggers and profilers.

The engine maintains ownership of the agent.

Calling this function will replace the existing agent, if any.

See also

agent()

Definition at line 4325 of file qscriptengine.cpp.

Referenced by QScriptDebuggerBackend::attachTo(), QScriptDebuggerBackend::detach(), QJSDebuggerAgent::QJSDebuggerAgent(), and QJSDebuggerAgent::~QJSDebuggerAgent().

{
    Q_D(QScriptEngine);
    if (agent && (agent->engine() != this)) {
        qWarning("QScriptEngine::setAgent(): "
                 "cannot set agent belonging to different engine");
        return;
    }
    QScript::APIShim shim(d);
    if (d->activeAgent)
        QScriptEngineAgentPrivate::get(d->activeAgent)->detach();
    d->activeAgent = agent;
    if (agent) {
        QScriptEngineAgentPrivate::get(agent)->attach();
    }
}

setDefaultPrototype()

void QScriptEngine::setDefaultPrototype	(	int	metaTypeId,
		const QScriptValue &	prototype
	)

Sets the default prototype of the C++ type identified by the given metaTypeId to prototype.

The default prototype provides a script interface for values of type metaTypeId when a value of that type is accessed from script code. Whenever the script engine (implicitly or explicitly) creates a QScriptValue from a value of type metaTypeId, the default prototype will be set as the QScriptValue's prototype.

The prototype object itself may be constructed using one of two principal techniques; the simplest is to subclass QScriptable, which enables you to define the scripting API of the type through QObject properties and slots. Another possibility is to create a script object by calling newObject(), and populate the object with the desired properties (e.g. native functions wrapped with newFunction()).

See also

defaultPrototype(), qScriptRegisterMetaType(), QScriptable, {Default Prototypes Example}

Definition at line 3010 of file qscriptengine.cpp.

Referenced by QScriptDBusMessageConstructor::QScriptDBusMessageConstructor().

{
    Q_D(QScriptEngine);
    d->setDefaultPrototype(metaTypeId, d->scriptValueToJSCValue(prototype));
}

setGlobalObject()

void QScriptEngine::setGlobalObject

(

const QScriptValue &

object

)

Sets this engine's Global Object to be the given object.

Since

4.5

If object is not a valid script object, this function does nothing.

When setting a custom global object, you may want to use QScriptValueIterator to copy the properties of the standard Global Object; alternatively, you can set the internal prototype of your custom object to be the original Global Object.

Definition at line 2053 of file qscriptengine.cpp.

Referenced by QDeclarativeGlobalScriptClass::explicitSetProperty(), QScriptDebuggerScriptedConsoleCommandJob::handleResponse(), QScriptDebuggerScriptedConsoleCommand::parse(), QDeclarativeGlobalScriptClass::QDeclarativeGlobalScriptClass(), QScriptContext::setThisObject(), and QScriptDebuggerScriptedConsoleCommandJob::start().

{
    Q_D(QScriptEngine);
    if (!object.isObject())
        return;
    QScript::APIShim shim(d);
    JSC::JSObject *jscObject = JSC::asObject(d->scriptValueToJSCValue(object));
    d->setGlobalObject(jscObject);
}

setProcessEventsInterval()

void QScriptEngine::setProcessEventsInterval

(

int

interval

)

Sets the interval between calls to QCoreApplication::processEvents to interval milliseconds.

While the interpreter is running, all event processing is by default blocked. This means for instance that the gui will not be updated and timers will not be fired. To allow event processing during interpreter execution one can specify the processing interval to be a positive value, indicating the number of milliseconds between each time QCoreApplication::processEvents() is called.

The default value is -1, which disables event processing during interpreter execution.

You can use QCoreApplication::postEvent() to post an event that performs custom processing at the next interval. For example, you could keep track of the total running time of the script and call abortEvaluation() when you detect that the script has been running for a long time without completing.

See also

processEventsInterval()

Definition at line 4156 of file qscriptengine.cpp.

{
    Q_D(QScriptEngine);
    d->processEventsInterval = interval;

    if (interval > 0)
        d->globalData->timeoutChecker->setCheckInterval(interval);

    d->timeoutChecker()->setShouldProcessEvents(interval > 0);
}

signalHandlerException

void QScriptEngine::signalHandlerException ( const QScriptValue &  exception )

signal

This signal is emitted when a script function connected to a signal causes an exception.

Since

4.4

See also

qScriptConnect()

toObject()

QScriptValue QScriptEngine::toObject

(

const QScriptValue &

value

)

Converts the given value to an object, if such a conversion is possible; otherwise returns an invalid QScriptValue.

Since

4.5

The conversion is performed according to the following table:

Input Type	Result
Undefined	An invalid QScriptValue.
Null	An invalid QScriptValue.
Boolean	A new Boolean object whose internal value is set to the value of the boolean.
Number	A new Number object whose internal value is set to the value of the number.
String	A new String object whose internal value is set to the value of the string.
Object	The result is the object itself (no conversion).

See also

newObject()

Definition at line 4401 of file qscriptengine.cpp.

Referenced by abortEvaluation(), and QScriptValue::toObject().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    JSC::JSValue jscValue = d->scriptValueToJSCValue(value);
    if (!jscValue || jscValue.isUndefined() || jscValue.isNull())
        return QScriptValue();
    JSC::ExecState* exec = d->currentFrame;
    JSC::JSValue result = jscValue.toObject(exec);
    return d->scriptValueFromJSCValue(result);
}

toScriptValue()

template<typename T >

QScriptValue QScriptEngine::toScriptValue ( const T &  value )

inline

Creates a QScriptValue with the given value.

Note that the template type T must be known to QMetaType.

See Conversion Between QtScript and C++ Types for a description of the built-in type conversion provided by QtScript. By default, the types that are not specially handled by QtScript are represented as QVariants (e.g. the value is passed to newVariant()); you can change this behavior by installing your own type conversion functions with qScriptRegisterMetaType().

See also

fromScriptValue(), qScriptRegisterMetaType()

Definition at line 213 of file qscriptengine.h.

Referenced by breakpointMapToScriptValue(), consoleCommandGroupMapToScriptValue(), consoleCommandToScriptValue(), QDeclarativeEnginePrivate::darker(), debuggerResponseToScriptValue(), debuggerScriptValuePropertyToScriptValue(), QDeclarativeXmlListModel::get(), QScriptDebuggerScriptedConsoleCommandJob::handleResponse(), QDeclarativeEnginePrivate::hsla(), QDeclarativeEnginePrivate::lighter(), FlatListScriptClass::property(), qScriptValueFromSequence(), QDeclarativeEnginePrivate::rgba(), scriptMapToScriptValue(), and QDeclarativeEnginePrivate::tint().

    {
        return qScriptValueFromValue(this, value);
    }

toStringHandle()

QScriptString QScriptEngine::toStringHandle

(

const QString &

str

)

Returns a handle that represents the given string, str.

Since

4.4

QScriptString can be used to quickly look up properties, and compare property names, of script objects.

See also

QScriptValue::property()

Definition at line 4372 of file qscriptengine.cpp.

Referenced by QDeclarativeSqlQueryScriptClass::QDeclarativeSqlQueryScriptClass().

{
    Q_D(QScriptEngine);
    QScript::APIShim shim(d);
    return d->toStringHandle(JSC::Identifier(d->currentFrame, str));
}

uncaughtException()

QScriptValue QScriptEngine::uncaughtException

(

)

const

Returns the current uncaught exception, or an invalid QScriptValue if there is no uncaught exception.

The exception value is typically an Error object; in that case, you can call toString() on the return value to obtain an error message.

See also

hasUncaughtException(), uncaughtExceptionLineNumber(),

Definition at line 2910 of file qscriptengine.cpp.

Referenced by QDeclarativeExpressionPrivate::exceptionToError(), QDeclarativeInclude::finished(), importExtension(), QDeclarativeInclude::include(), uncaughtExceptionBacktrace(), uncaughtExceptionLineNumber(), and QDeclarativeInclude::worker_include().

{
    Q_D(const QScriptEngine);
    QScriptValue result;
    JSC::ExecState* exec = d->globalExec();
    if (exec->hadException())
        result = const_cast<QScriptEnginePrivate*>(d)->scriptValueFromJSCValue(exec->exception());
    else
        result = d->currentException();
    return result;
}

uncaughtExceptionBacktrace()

QStringList QScriptEngine::uncaughtExceptionBacktrace

(

)

const

Returns a human-readable backtrace of the last uncaught exception.

It is in the form <function-name>()<file-name>:<line-number>.

See also

uncaughtException()

Definition at line 2944 of file qscriptengine.cpp.

{
    if (!hasUncaughtException())
        return QStringList();
// ### currently no way to get a full backtrace from JSC without installing a
// debugger that reimplements exception() and store the backtrace there.
    QScriptValue value = uncaughtException();
    if (!value.isError())
        return QStringList();
    QStringList result;
    result.append(QString::fromLatin1("<anonymous>()@%0:%1")
                  .arg(value.property(QLatin1String("fileName")).toString())
                  .arg(value.property(QLatin1String("lineNumber")).toInt32()));
    return result;
}

uncaughtExceptionLineNumber()

int QScriptEngine::uncaughtExceptionLineNumber

(

)

const

Returns the line number where the last uncaught exception occurred.

Line numbers are 1-based, unless a different base was specified as the second argument to evaluate().

See also

hasUncaughtException()

Definition at line 2930 of file qscriptengine.cpp.

Referenced by QDeclarativeExpressionPrivate::exceptionToError(), and QScriptDebuggerScriptedConsoleCommand::parse().

{
    if (!hasUncaughtException())
        return -1;
    return uncaughtException().property(QLatin1String("lineNumber")).toInt32();
}

undefinedValue()

QScriptValue QScriptEngine::undefinedValue

(

)

Returns a QScriptValue of the primitive type Undefined.

See also

nullValue()

Definition at line 2079 of file qscriptengine.cpp.

Referenced by Node::attributes(), Node::childNodes(), QDeclarativeObjectMethodScriptClass::connect(), consoleCommandToScriptValue(), QDeclarativeObjectScriptClass::destroy(), QDeclarativeObjectMethodScriptClass::disconnect(), Document::documentElement(), QScriptDebuggerBackendPrivate::fileName(), Node::firstChild(), FlatListModel::get(), QDeclarativeXmlListModel::get(), NestedListModel::get(), importExtension(), QDeclarativeInclude::include(), Text::isElementContentWhitespace(), Node::lastChild(), NamedNodeMap::length(), NodeList::length(), CharacterData::length(), Attr::name(), QDeclarativeObjectScriptClass::newQObject(), Node::nextSibling(), Node::nodeName(), Node::nodeType(), Node::nodeValue(), QDeclarativeWorkerScriptEnginePrivate::onMessage(), Attr::ownerElement(), Node::parentNode(), Node::previousSibling(), QDeclarativeObjectMethodScriptClass::property(), QDeclarativeSqlQueryScriptClass::property(), qmlsqldatabase_change_version(), qmlsqldatabase_item(), qmlsqldatabase_open_sync(), qmlsqldatabase_transaction_shared(), qmlxmlhttprequest_new(), qmlxmlhttprequest_setRequestHeader(), QDeclarativeWorkerScriptEnginePrivate::sendMessage(), QScriptDebuggerValue::toScriptValue(), QScriptDebuggerBackendPrivate::trace(), Attr::value(), Text::wholeText(), QDeclarativeInclude::worker_include(), Document::xmlEncoding(), Document::xmlStandalone(), and Document::xmlVersion().

{
    Q_D(QScriptEngine);
    return d->scriptValueFromJSCValue(JSC::jsUndefined());
}

Friends and Related Functions

FunctionSignature()

FunctionSignature

related

The function signature QScriptValue f(QScriptContext *, QScriptEngine *).

A function with such a signature can be passed to QScriptEngine::newFunction() to wrap the function.

FunctionWithArgSignature()

FunctionWithArgSignature

related

The function signature QScriptValue f(QScriptContext *, QScriptEngine *, void *).

A function with such a signature can be passed to QScriptEngine::newFunction() to wrap the function.

qScriptConnect()

bool qScriptConnect ( QObject *  sender, const char *  signal, const QScriptValue &  receiver, const QScriptValue &  function  )

related

Creates a connection from the signal in the sender to the given function.

Since

4.4

If receiver is an object, it will act as the `this' object when the signal handler function is invoked. Returns true if the connection succeeds; otherwise returns false.

See also

qScriptDisconnect(), QScriptEngine::signalHandlerException()

Definition at line 4242 of file qscriptengine.cpp.

{
    if (!sender || !signal)
        return false;
    if (!function.isFunction())
        return false;
    if (receiver.isObject() && (receiver.engine() != function.engine()))
        return false;
    QScriptEnginePrivate *engine = QScriptEnginePrivate::get(function.engine());
    QScript::APIShim shim(engine);
    JSC::JSValue jscReceiver = engine->scriptValueToJSCValue(receiver);
    JSC::JSValue jscFunction = engine->scriptValueToJSCValue(function);
    return engine->scriptConnect(sender, signal, jscReceiver, jscFunction,
                                 Qt::AutoConnection);
}

qScriptDisconnect()

bool qScriptDisconnect ( QObject *  sender, const char *  signal, const QScriptValue &  receiver, const QScriptValue &  function  )

related

Disconnects the signal in the sender from the given (receiver, function) pair.

Since

4.4

Returns true if the connection is successfully broken; otherwise returns false.

See also

qScriptConnect()

Definition at line 4272 of file qscriptengine.cpp.

{
    if (!sender || !signal)
        return false;
    if (!function.isFunction())
        return false;
    if (receiver.isObject() && (receiver.engine() != function.engine()))
        return false;
    QScriptEnginePrivate *engine = QScriptEnginePrivate::get(function.engine());
    QScript::APIShim shim(engine);
    JSC::JSValue jscReceiver = engine->scriptValueToJSCValue(receiver);
    JSC::JSValue jscFunction = engine->scriptValueToJSCValue(function);
    return engine->scriptDisconnect(sender, signal, jscReceiver, jscFunction);
}

qScriptRegisterMetaType()

int qScriptRegisterMetaType ( QScriptEngine *  engine, QScriptValue(*)(QScriptEngine *, const T &t)  toScriptValue, void(*)(const QScriptValue &, T &t)  fromScriptValue, const QScriptValue &  prototype = QScriptValue()  )

related

Registers the type T in the given engine. toScriptValue must be a function that will convert from a value of type T to a QScriptValue, and fromScriptValue a function that does the opposite. prototype, if valid, is the prototype that's set on QScriptValues returned by toScriptValue.

Returns the internal ID used by QMetaType.

You only need to call this function if you want to provide custom conversion of values of type T, i.e. if the default QVariant-based representation and conversion is not appropriate. (Note that custom QObject-derived types also fall in this category; e.g. for a QObject-derived class called MyObject, you probably want to define conversion functions for MyObject* that utilize QScriptEngine::newQObject() and QScriptValue::toQObject().)

If you only want to define a common script interface for values of type T, and don't care how those values are represented (i.e. storing them in QVariants is fine), use setDefaultPrototype() instead; this will minimize conversion costs.

You need to declare the custom type first with Q_DECLARE_METATYPE().

After a type has been registered, you can convert from a QScriptValue to that type using fromScriptValue(), and create a QScriptValue from a value of that type using toScriptValue(). The engine will take care of calling the proper conversion function when calling C++ slots, and when getting or setting a C++ property; i.e. the custom type may be used seamlessly on both the C++ side and the script side.

The following is an example of how to use this function. We will specify custom conversion of our type MyStruct. Here's the C++ type:

struct MyStruct {
    int x;
    int y;
};

We must declare it so that the type will be known to QMetaType:

Q_DECLARE_METATYPE(MyStruct)

Next, the MyStruct conversion functions. We represent the MyStruct value as a script object and just copy the properties:

QScriptValue toScriptValue(QScriptEngine *engine, const MyStruct &s)
{
  QScriptValue obj = engine->newObject();
  obj.setProperty("x", s.x);
  obj.setProperty("y", s.y);
  return obj;
}

void fromScriptValue(const QScriptValue &obj, MyStruct &s)
{
  s.x = obj.property("x").toInt32();
  s.y = obj.property("y").toInt32();
}

Now we can register MyStruct with the engine:

qScriptRegisterMetaType(engine, toScriptValue, fromScriptValue);

Working with MyStruct values is now easy:

MyStruct s = qscriptvalue_cast<MyStruct>(context->argument(0));
...
MyStruct s2;
s2.x = s.x + 10;
s2.y = s.y + 20;
QScriptValue v = engine->toScriptValue(s2);

If you want to be able to construct values of your custom type from script code, you have to register a constructor function for the type. For example:

QScriptValue createMyStruct(QScriptContext *, QScriptEngine *engine)
{
    MyStruct s;
    s.x = 123;
    s.y = 456;
    return engine->toScriptValue(s);
}
...
QScriptValue ctor = engine.newFunction(createMyStruct);
engine.globalObject().setProperty("MyStruct", ctor);

See also

qScriptRegisterSequenceMetaType(), qRegisterMetaType()

Definition at line 380 of file qscriptengine.h.

{
    const int id = qRegisterMetaType<T>(); // make sure it's registered

    qScriptRegisterMetaType_helper(
        eng, id, reinterpret_cast<QScriptEngine::MarshalFunction>(toScriptValue),
        reinterpret_cast<QScriptEngine::DemarshalFunction>(fromScriptValue),
        prototype);

    return id;
}

qScriptRegisterMetaType_helper

void qScriptRegisterMetaType_helper ( QScriptEngine *  eng, int  type, QScriptEngine::MarshalFunction  mf, QScriptEngine::DemarshalFunction  df, const QScriptValue &  prototype  )

friend

Definition at line 371 of file qscriptengine.h.

{
    eng->registerCustomType(type, mf, df, prototype);
}

qScriptRegisterSequenceMetaType()

int qScriptRegisterSequenceMetaType ( QScriptEngine *  engine, const QScriptValue &  prototype = QScriptValue()  )

related

Registers the sequence type T in the given engine. This function provides conversion functions that convert between T and Qt Script Array objects. T must provide a const_iterator class and begin(), end() and push_back() functions. If prototype is valid, it will be set as the prototype of Array objects due to conversion from T; otherwise, the standard Array prototype will be used.

Returns the internal ID used by QMetaType.

You need to declare the container type first with Q_DECLARE_METATYPE(). If the element type isn't a standard Qt/C++ type, it must be declared using Q_DECLARE_METATYPE() as well. Example:

Q_DECLARE_METATYPE(QVector<int>)

...

qScriptRegisterSequenceMetaType<QVector<int> >(engine);
...
QVector<int> v = qscriptvalue_cast<QVector<int> >(engine->evaluate("[5, 1, 3, 2]"));
qSort(v.begin(), v.end());
QScriptValue a = engine->toScriptValue(v);
qDebug() << a.toString(); // outputs "[1, 2, 3, 5]"

See also

qScriptRegisterMetaType()

Definition at line 424 of file qscriptengine.h.

{
    return qScriptRegisterMetaType<T>(engine, qScriptValueFromSequence,
                                      qScriptValueToSequence, prototype);
}

qscriptvalue_cast_helper

bool qscriptvalue_cast_helper ( const QScriptValue &  value, int  type, void *  ptr  )

friend

Definition at line 338 of file qscriptengine.h.

{
    return QScriptEngine::convertV2(value, type, ptr);
}

qScriptValueFromQMetaObject()

QScriptValue qScriptValueFromQMetaObject ( QScriptEngine *  engine )

related

Since

4.3

Uses engine to create a QScriptValue that represents the Qt class T.

This function is equivalent to QScriptEngine::scriptValueFromQMetaObject().

Note

This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code.

See also

QScriptEngine::newQMetaObject()

Definition at line 305 of file qscriptengine.h.

{
    return engine->scriptValueFromQMetaObject<T>();
}

qScriptValueFromSequence()

QScriptValue qScriptValueFromSequence ( QScriptEngine *  engine, const Container &  container  )

related

Since

4.3

Creates an array in the form of a QScriptValue using the given engine with the given container of template type Container.

The Container type must provide a const_iterator class to enable the contents of the container to be copied into the array.

Additionally, the type of each element in the sequence should be suitable for conversion to a QScriptValue. See Conversion Between QtScript and C++ Types for more information about the restrictions on types that can be used with QScriptValue.

See also

QScriptEngine::fromScriptValue()

Definition at line 401 of file qscriptengine.h.

{
    QScriptValue a = eng->newArray();
    typename Container::const_iterator begin = cont.begin();
    typename Container::const_iterator end = cont.end();
    typename Container::const_iterator it;
    quint32 i;
    for (it = begin, i = 0; it != end; ++it, ++i)
        a.setProperty(i, eng->toScriptValue(*it));
    return a;
}

qScriptValueFromValue()

QScriptValue qScriptValueFromValue ( QScriptEngine *  engine, const T &  value  )

related

Since

4.3

Creates a QScriptValue using the given engine with the given value of template type T.

This function is equivalent to QScriptEngine::toScriptValue().

Note

This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code.

See also

QScriptEngine::toScriptValue(), qscriptvalue_cast()

Definition at line 327 of file qscriptengine.h.

Referenced by qscriptQMetaObjectConstructor().

{
    return qScriptValueFromValue_helper(engine, qMetaTypeId<T>(), &t);
}

qScriptValueFromValue_helper

QScriptValue qScriptValueFromValue_helper ( QScriptEngine *  engine, int  type, const void *  ptr  )

friend

Definition at line 318 of file qscriptengine.h.

{
    if (!engine)
        return QScriptValue();

    return engine->create(type, ptr);
}

qScriptValueToSequence()

void qScriptValueToSequence ( const QScriptValue &  value, Container &  container  )

related

Copies the elements in the sequence specified by value to the given container of template type Container.

Since

4.3

The value used is typically an array, but any container can be copied as long as it provides a length property describing how many elements it contains.

Additionally, the type of each element in the sequence must be suitable for conversion to a C++ type from a QScriptValue. See Conversion Between QtScript and C++ Types for more information about the restrictions on types that can be used with QScriptValue.

See also

qscriptvalue_cast()

Definition at line 414 of file qscriptengine.h.

{
    quint32 len = value.property(QLatin1String("length")).toUInt32();
    for (quint32 i = 0; i < len; ++i) {
        QScriptValue item = value.property(i);
        cont.push_back(qscriptvalue_cast<typename Container::value_type>(item));
    }
}

qScriptValueToValue()

T qScriptValueToValue ( const QScriptValue &  value )

related

Returns the given value converted to the template type T.

Since

4.3

This function is equivalent to QScriptEngine::fromScriptValue().

Note

This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code.

See also

QScriptEngine::fromScriptValue()

Definition at line 365 of file qscriptengine.h.

{
    return qscriptvalue_cast<T>(value);
}

---

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

• /src/script/api/qscriptengine.h
• /src/script/api/qscriptengine.cpp