QScriptString Class Reference

The QScriptString class acts as a handle to "interned" strings in a QScriptEngine. More...

#include <qscriptstring.h>

Public Functions
bool	isValid () const
	Returns true if this QScriptString is valid; otherwise returns false. More...
	operator QString () const
	Returns the string that this QScriptString represents, or a null string if this QScriptString is not valid. More...
bool	operator!= (const QScriptString &other) const
	Returns true if this QScriptString is not equal to other; otherwise returns false. More...
QScriptString &	operator= (const QScriptString &other)
	Assigns the other value to this QScriptString. More...
bool	operator== (const QScriptString &other) const
	Returns true if this QScriptString is equal to other; otherwise returns false. More...
	QScriptString ()
	Constructs an invalid QScriptString. More...
	QScriptString (const QScriptString &other)
	Constructs a new QScriptString that is a copy of other. More...
quint32	toArrayIndex (bool *ok=0) const
QString	toString () const
	Returns the string that this QScriptString represents, or a null string if this QScriptString is not valid. More...
	~QScriptString ()
	Destroys this QScriptString. More...

Properties
QExplicitlySharedDataPointer< QScriptStringPrivate >	d_ptr

Friends
class	QScriptValue

Detailed Description

The QScriptString class acts as a handle to "interned" strings in a QScriptEngine.

Since

4.4

QScriptString can be used to achieve faster (repeated) property getting/setting, and comparison of property names, of script objects.

To get a QScriptString representation of a string, pass the string to QScriptEngine::toStringHandle(). The typical usage pattern is to register one or more pre-defined strings when setting up your script environment, then subsequently use the relevant QScriptString as argument to e.g. QScriptValue::property().

Call the toString() function to obtain the string that a QScriptString represents.

Call the toArrayIndex() function to convert a QScriptString to an array index. This is useful when using QScriptClass to implement array-like objects.

Definition at line 38 of file qscriptstring.h.

Constructors and Destructors

QScriptString() [1/2]

QScriptString::QScriptString

(

)

Constructs an invalid QScriptString.

Definition at line 65 of file qscriptstring.cpp.

    : d_ptr(0)
{
}

QScriptString() [2/2]

QScriptString::QScriptString

(

const QScriptString &

other

)

Constructs a new QScriptString that is a copy of other.

Definition at line 73 of file qscriptstring.cpp.

    : d_ptr(other.d_ptr)
{
    if (d_func() && (d_func()->type == QScriptStringPrivate::StackAllocated)) {
        Q_ASSERT(d_func()->ref != 1);
        d_ptr.detach();
        d_func()->ref = 1;
        d_func()->type = QScriptStringPrivate::HeapAllocated;
        d_func()->engine->registerScriptString(d_func());
    }
}

~QScriptString()

QScriptString::~QScriptString

(

)

Destroys this QScriptString.

Definition at line 88 of file qscriptstring.cpp.

{
    Q_D(QScriptString);
    if (d) {
        switch (d->type) {
        case QScriptStringPrivate::StackAllocated:
            Q_ASSERT(d->ref == 1);
            d->ref.ref(); // avoid deletion
            break;
        case QScriptStringPrivate::HeapAllocated:
            if (d->engine && (d->ref == 1)) {
                // Make sure the identifier is removed from the correct engine.
                QScript::APIShim shim(d->engine);
                d->identifier = JSC::Identifier();
                d->engine->unregisterScriptString(d);
            }
            break;
        }
    }
}

Functions

isValid()

bool QScriptString::isValid

(

)

const

Returns true if this QScriptString is valid; otherwise returns false.

Definition at line 133 of file qscriptstring.cpp.

{
    return QScriptStringPrivate::isValid(*this);
}

operator QString()

QScriptString::operator QString

(

)

const

Returns the string that this QScriptString represents, or a null string if this QScriptString is not valid.

See also

toString()

Definition at line 204 of file qscriptstring.cpp.

{
    return toString();
}

operator!=()

bool QScriptString::operator!=

(

const QScriptString &

other

)

const

Returns true if this QScriptString is not equal to other; otherwise returns false.

Definition at line 154 of file qscriptstring.cpp.

{
    return !operator==(other);
}

operator=()

QScriptString & QScriptString::operator=

(

const QScriptString &

other

)

Assigns the other value to this QScriptString.

Definition at line 112 of file qscriptstring.cpp.

{
    if (d_func() && d_func()->engine && (d_func()->ref == 1) && (d_func()->type == QScriptStringPrivate::HeapAllocated)) {
        // current d_ptr will be deleted at the assignment below, so unregister it first
        d_func()->engine->unregisterScriptString(d_func());
    }
    d_ptr = other.d_ptr;
    if (d_func() && (d_func()->type == QScriptStringPrivate::StackAllocated)) {
        Q_ASSERT(d_func()->ref != 1);
        d_ptr.detach();
        d_func()->ref = 1;
        d_func()->type = QScriptStringPrivate::HeapAllocated;
        d_func()->engine->registerScriptString(d_func());
    }
    return *this;
}

operator==()

bool QScriptString::operator==

(

const QScriptString &

other

)

const

Returns true if this QScriptString is equal to other; otherwise returns false.

Definition at line 142 of file qscriptstring.cpp.

Referenced by operator!=().

{
    Q_D(const QScriptString);
    if (!d || !other.d_func())
        return d == other.d_func();
    return d->identifier == other.d_func()->identifier;
}

toArrayIndex()

quint32 QScriptString::toArrayIndex

(

bool *

ok = 0

)

const

Since

4.6

Attempts to convert this QScriptString to a QtScript array index, and returns the result.

If a conversion error occurs, *{ok} is set to false; otherwise {ok} is set to true.

Definition at line 168 of file qscriptstring.cpp.

{
    Q_D(const QScriptString);
    if (!d) {
        if (ok)
            *ok = false;
        return -1;
    }
    bool tmp;
    bool *okok = ok ? ok : &tmp;
    quint32 result = d->identifier.toArrayIndex(okok);
    if (!*okok)
        result = -1;
    return result;
}

toString()

QString QScriptString::toString

(

)

const

Returns the string that this QScriptString represents, or a null string if this QScriptString is not valid.

See also

isValid()

Definition at line 190 of file qscriptstring.cpp.

Referenced by QScript::ClassObjectDelegate::getOwnPropertyNames(), operator QString(), NamedNodeMapClass::queryProperty(), NodeListClass::queryProperty(), QDeclarativeGlobalScriptClass::setProperty(), and QScriptValue::setProperty().

{
    Q_D(const QScriptString);
    if (!d || !d->engine)
        return QString();
    return d->identifier.ustring();
}

Friends and Related Functions

QScriptValue

friend class QScriptValue

friend

Definition at line 59 of file qscriptstring.h.

Properties

d_ptr

QExplicitlySharedDataPointer<QScriptStringPrivate> QScriptString::d_ptr

private

Definition at line 58 of file qscriptstring.h.

Referenced by QScriptStringPrivate::init(), QScriptStringPrivate::isValid(), operator=(), QScriptValue::property(), QScriptValue::propertyFlags(), QScriptString(), and QScriptValue::setProperty().

---

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

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