cbor.qdoc

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
    \group cbor
    \title CBOR Support in Qt
    \ingroup qt-basic-concepts
    \brief An overview of CBOR support in Qt.
    \ingroup explanations-dataprocessingandio
 
    \ingroup frameworks-technologies
 
    \keyword CBOR
 
    Qt provides support for dealing with CBOR data. CBOR is a binary format to
    store data that has a superset of the types available in JSON, but is more
    compact.
 
    The CBOR support in Qt provides an easy to use C++ API to parse,
    modify and save CBOR data.
 
    More details about the CBOR data format can be found in \l {RFC 7049}.
 
    \section1 Overview
 
    CBOR is a format to store structured data. It has three groups of built-in types:
 
    \list
    \li Basic types: integers, floating point, boolean, null, etc.
    \li String-like types: strings and byte arrays
    \li Containers: arrays and maps
    \endlist
 
    In addition, CBOR can add a "tag" to extend the meaning of the type. The
    container types can contain basic types, string-like types and containers.
 
    \sa {Parsing and displaying CBOR data}, {Serialization Converter}, {Saving and Loading a Game}
 
    \section1 The CBOR Classes
 
    \section2 The QCborValue Class
 
    The QCborValue class represents any CBOR type. It also has a simple API for
    reading and writing to QCborStreamReader and QCborStreamWriter objects, as
    well as manipulating such objects in memory, with the help of QCborArray
    and QCborMap. The CborValue API is simplified from the full CBOR data type
    and always represents all integers as \l qint64 and all floating-point as
    \c double. This means QCborValue is unable to represent CBOR integer values
    outside of the range of \l qint64 (-2^63 to 2^63-1). When creating a CBOR
    stream, QCborValue::toCbor() can be configured to attempt to write the
    shorter single- and half-precision floating-point representations.
 
    \section2 The QCborArray Class
 
    The QCborArray class is used to hold an array of QCborValue objects. A
    QCborValue object can contain a QCborArray object. It has functions for
    converting to and from QVariantList, QStringList, QJsonArray.
 
    \section2 The QCborMap Class
 
    The QCborMap class is used to hold an map of QCborValue objects. A
    QCborValue object can contain a QCborMap object. It has functions for
    converting to and from QVariantMap, QVariantHash, and QJsonObject, but it
    can have keys of any type, not just QString.
 
    \section2 The QCborStreamReader Class
 
    The QCborStreamReader class is a low level API for reading CBOR data from a
    QIODevice, a QByteArray, or a pointer to memory. It has an API similar to
    the QXmlStreamReader class.
 
    \section2 The QCborStreamWriter Class
 
    The QCborStreamWriter class is a low level API for writing CBOR data to a
    QIODevice or a QByteArray. It has an API similar to the QXmlStreamWriter
    class.
*/