TagLib::Variant Class Reference

An implicitly shared discriminated union. More...

#include <tvariant.h>

Public Types
enum	Type {   Void , Bool , Int , UInt ,   LongLong , ULongLong , Double , String ,   StringList , ByteVector , ByteVectorList , VariantList ,   VariantMap }

Public Member Functions
	Variant ()
	Variant (int val)
	Variant (unsigned int val)
	Variant (long long val)
	Variant (unsigned long long val)
	Variant (bool val)
	Variant (double val)
	Variant (const char *val)
	Variant (const TagLib::String &val)
	Variant (const TagLib::StringList &val)
	Variant (const TagLib::ByteVector &val)
	Variant (const TagLib::ByteVectorList &val)
	Variant (const TagLib::List< TagLib::Variant > &val)
	Variant (const TagLib::Map< TagLib::String, TagLib::Variant > &val)
	Variant (const Variant &v)
	~Variant ()
Type	type () const
bool	isEmpty () const
int	toInt (bool *ok=nullptr) const
unsigned int	toUInt (bool *ok=nullptr) const
long long	toLongLong (bool *ok=nullptr) const
unsigned long long	toULongLong (bool *ok=nullptr) const
bool	toBool (bool *ok=nullptr) const
double	toDouble (bool *ok=nullptr) const
TagLib::String	toString (bool *ok=nullptr) const
TagLib::StringList	toStringList (bool *ok=nullptr) const
TagLib::ByteVector	toByteVector (bool *ok=nullptr) const
TagLib::ByteVectorList	toByteVectorList (bool *ok=nullptr) const
TagLib::List< TagLib::Variant >	toList (bool *ok=nullptr) const
TagLib::Map< TagLib::String, TagLib::Variant >	toMap (bool *ok=nullptr) const
template<typename T>
T	value (bool *ok=nullptr) const
bool	operator== (const Variant &v) const
bool	operator!= (const Variant &v) const
Variant &	operator= (const Variant &v)

Friends
TAGLIB_EXPORT std::ostream &	operator<< (std::ostream &s, const TagLib::Variant &v)

Related Symbols
(Note that these are not member symbols.)
TAGLIB_EXPORT std::ostream &	operator<< (std::ostream &s, const TagLib::Variant &v)

Detailed Description

An implicitly shared discriminated union.

This is an implicitly shared discriminated union.

The use of implicit sharing means that copying a variant is cheap. These Variant objects are immutable (have only const methods).

Member Enumeration Documentation

Type

enum TagLib::Variant::Type

Types which can be stored in a variant.

Enumerator
Void	variant is empty
Bool	bool
Int	int
UInt	unsigned int
LongLong	long long
ULongLong	unsigned long long
Double	double
String	String.
StringList	StringList.
ByteVector	ByteVector.
ByteVectorList	ByteVectorList.
VariantList	VariantList
VariantMap	VariantMap

Constructor & Destructor Documentation

Variant() [1/15]

TagLib::Variant::Variant

(

)

Constructs an empty Variant.

Referenced by operator!=(), operator=(), operator==(), and Variant().

Variant() [2/15]

TagLib::Variant::Variant

(

int

val

)

Variant() [3/15]

TagLib::Variant::Variant

(

unsigned int

val

)

Variant() [4/15]

TagLib::Variant::Variant

(

long long

val

)

Variant() [5/15]

TagLib::Variant::Variant

(

unsigned long long

val

)

Variant() [6/15]

TagLib::Variant::Variant

(

bool

val

)

Variant() [7/15]

TagLib::Variant::Variant

(

double

val

)

Variant() [8/15]

TagLib::Variant::Variant

(

const char *

val

)

Variant() [9/15]

TagLib::Variant::Variant

(

const TagLib::String &

val

)

Variant() [10/15]

TagLib::Variant::Variant

(

const TagLib::StringList &

val

)

Variant() [11/15]

TagLib::Variant::Variant

(

const TagLib::ByteVector &

val

)

Variant() [12/15]

TagLib::Variant::Variant

(

const TagLib::ByteVectorList &

val

)

Variant() [13/15]

TagLib::Variant::Variant

(

const TagLib::List< TagLib::Variant > &

val

)

Variant() [14/15]

TagLib::Variant::Variant

(

const TagLib::Map< TagLib::String, TagLib::Variant > &

val

)

Variant() [15/15]

TagLib::Variant::Variant

(

const Variant &

v

)

Make a shallow, implicitly shared, copy of v. Because this is implicitly shared, this method is lightweight and suitable for pass-by-value usage.

References Variant().

~Variant()

TagLib::Variant::~Variant

(

)

Destroys this Variant instance.

Member Function Documentation

isEmpty()

bool TagLib::Variant::isEmpty

(

)

const

Returns true if the Variant is empty.

operator!=()

bool TagLib::Variant::operator!=

(

const Variant &

v

)

const

Returns true if the Variant and v differ in type or value.

References Variant().

operator=()

Variant & TagLib::Variant::operator=

(

const Variant &

v

)

Performs a shallow, implicitly shared, copy of v, overwriting the Variant's current data.

References Variant().

operator==()

bool TagLib::Variant::operator==

(

const Variant &

v

)

const

Returns true if the Variant and v are of the same type and contain the same value.

References Variant().

toBool()

bool TagLib::Variant::toBool

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toByteVector()

TagLib::ByteVector TagLib::Variant::toByteVector

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toByteVectorList()

TagLib::ByteVectorList TagLib::Variant::toByteVectorList

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toDouble()

double TagLib::Variant::toDouble

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toInt()

int TagLib::Variant::toInt

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toList()

TagLib::List< TagLib::Variant > TagLib::Variant::toList

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toLongLong()

long long TagLib::Variant::toLongLong

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toMap()

TagLib::Map< TagLib::String, TagLib::Variant > TagLib::Variant::toMap

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toString()

TagLib::String TagLib::Variant::toString

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toStringList()

TagLib::StringList TagLib::Variant::toStringList

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toUInt()

unsigned int TagLib::Variant::toUInt

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

toULongLong()

unsigned long long TagLib::Variant::toULongLong

(

bool *

ok = nullptr

)

const

Extracts a value from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

type()

Type TagLib::Variant::type

(

)

const

Get the type which is currently stored in this Variant.

value()

template<typename T>

template TAGLIB_EXPORT VariantMap TagLib::Variant::value

(

bool *

ok = nullptr

)

const

Extracts value of type T from the Variant. If ok is passed, its boolean variable will be set to true if the Variant contains the correct type, and the returned value is the value of the Variant. Otherwise, the ok variable is set to false and a dummy default value is returned.

Friends And Related Symbol Documentation

operator<< [1/2]

TAGLIB_EXPORT std::ostream & operator<< ( std::ostream & s, const TagLib::Variant & v )

friend

References TAGLIB_EXPORT, and TAGLIB_MSVC_SUPPRESS_WARNING_NEEDS_TO_HAVE_DLL_INTERFACE.

operator<<() [2/2]

TAGLIB_EXPORT std::ostream & operator<< ( std::ostream & s, const TagLib::Variant & v )

related

Send the variant to an output stream.

References ByteVector, ByteVectorList, String, StringList, and TAGLIB_EXPORT.

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

• tvariant.h