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* qhashfunctions.h: add specializations of std::hash for some Qt typesMarc Mutz2019-05-291-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have a problem. Our types don't play well with the std unordered containers, because they do not specialize std::hash. We therefore force our users to come up with an implementation, hindering interoperability, since any two developers are unlikely to come up with compatible implementations. So combining libraries written by different developers will result in ODR violations. Now that we depend on C++11, and thus the presence of std::hash, we still face the problem that the standard does not provide us with a means to compose new hash functions out of old ones. In particular, we cannot, yet, depend on C++17's std::hash<std::string_view> to implement std::hash<QByteArray>, say. There's also no std::hash for std::tuple, which would allow easy composition by using std::tie(). So piggy-back on the work we have done over the years on qHash() functions, and implement the std::hash specializations for Qt types using the existing qHash() functions, with a twist: The standard allows implementations to provide means against predictable hash values. Qt has this, too, but the seed is managed by the container and passed to the qHash() function as a separate argument. The standard does not have this explicit seed, so any protection must be implicit in the normal use of std::hash. To reap whatever protection that std library has on offer, if any, we calculate a seed value by hashing int(0). This will be subject to constant folding if there's no actual seed, but will produce a value dependent on the seed if there is one. Add some tests. A question that remains is how to document the specialization. Can we have a \stdhashable QDoc macro that does everything for us? Task-number: QTBUG-33428 Change-Id: Idfe775f1661f8489587353c4b148d76611ac76f3 Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io> Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
* Merge "Merge remote-tracking branch 'origin/5.13' into dev" into ↵Qt Forward Merge Bot2019-04-041-26/+26
|\ | | | | | | refs/staging/dev
| * Replace Q_DECL_NOEXCEPT with noexcept in corelibAllan Sandfeld Jensen2019-04-031-26/+26
| | | | | | | | | | | | | | In preparation of Qt6 move away from pre-C++11 macros. Change-Id: I44126693c20c18eca5620caab4f7e746218e0ce3 Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
* | Remove remaining Q_DECL_NOEXCEPT/Q_DECL_NOTHROW usageAllan Sandfeld Jensen2019-04-041-7/+7
|/ | | | | Change-Id: I91ac9e714a465cab226b211812aa46e8fe5ff2ab Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
* JSON: Add qHash functions for JSON and CBOR typesUlf Hermann2018-08-271-0/+5
| | | | | | | This way we can easily use them as keys in QHash and QSet. Change-Id: Ie744c3b5ad1176ba2ab035c7e650af483757a0c9 Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
* doc: Fix three "Cannot tie" errorsMartin Smith2017-12-021-1/+1
| | | | | | | | | | Two of the three functions were for functions that should not be documented. The third was a function protected by #ifndef Q_OS_DARWIN, which required a test of Q_CLANG_QDOC in the header and cpp files. Change-Id: Id2ab3e4f2ea896dc628a622de2e80a19c18eb9fe Reviewed-by: Topi Reiniö <topi.reinio@qt.io>
* Allow to chain qt_hash() callsMarc Mutz2017-03-301-1/+1
| | | | | | | | | There are some callers of qt_hash that first build a string just to hash it. By allowing to pass an initial value for 'h', we can chain qt_hash() calls to avoid having to allocate memory just to hash a two-part string. Change-Id: Ifaca82d47b2fb8c707912342c3ddd84f91e70267 Reviewed-by: Lars Knoll <lars.knoll@qt.io>
* Add qHash(QStringView)Marc Mutz2017-03-301-1/+4
| | | | | | | | [ChangeLog][QtCore] Added qHash(QStringView). Change-Id: I69c9203cf301fe586e924168381884aab2e19e5c Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com> Reviewed-by: Anton Kudryavtsev <antkudr@mail.ru>
* Replace internal qt_hash(QString(Ref)) functions with one taking QStringViewMarc Mutz2017-03-301-2/+1
| | | | | | Change-Id: I49d07689e642d26b4bceda5cace738aadd828ce0 Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com> Reviewed-by: Anton Kudryavtsev <antkudr@mail.ru>
* Merge remote-tracking branch 'origin/5.6' into 5.7Liang Qi2016-05-191-0/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: configure src/3rdparty/angle/src/libANGLE/renderer/d3d/d3d11/Renderer11.cpp src/network/access/qnetworkaccessmanager.cpp src/plugins/platforms/cocoa/qcocoacolordialoghelper.mm src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmcursor.cpp src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmsgbmcursor.h src/widgets/widgets/qlineedit_p.cpp src/widgets/widgets/qlineedit_p.h src/winmain/winmain.pro tests/auto/corelib/io/qstorageinfo/tst_qstorageinfo.cpp tests/auto/dbus/qdbusconnection/tst_qdbusconnection.cpp tests/auto/dbus/qdbusconnection/tst_qdbusconnection.h tests/auto/testlib/selftests/expected_cmptest.teamcity tests/auto/testlib/selftests/expected_cmptest.txt tests/auto/widgets/itemviews/qtableview/tst_qtableview.cpp tools/configure/configureapp.cpp Change-Id: Ib9997b0d0f91946e4081d36c0c6b696c5c983b2a
| * Move q{Set,}GlobalQHashSeed() to the correct header fileMarc Mutz2016-05-131-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The <QHash> only contains the container these days, while <QHashFunctions> contains the qHash() function overloads and related functions. This is where these two functions belong, too. This change is BC and SC, since qhash.h includes qhashfunctions.h. Change-Id: I2e7febb0ffca209af67fb9f2cd363596867a44e1 Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com> Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
* | Updated license headersJani Heikkinen2016-01-151-14/+20
| | | | | | | | | | | | | | | | | | | | | | From Qt 5.7 -> LGPL v2.1 isn't an option anymore, see http://blog.qt.io/blog/2016/01/13/new-agreement-with-the-kde-free-qt-foundation/ Updated license headers to use new LGPL header instead of LGPL21 one (in those files which will be under LGPL v3) Change-Id: I046ec3e47b1876cd7b4b0353a576b352e3a946d9 Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>
* | Add qHash(std::pair)Marc Mutz2015-12-301-0/+9
|/ | | | | | | | | | | We already include <utility> in <qglobal.h>, so we might as well provide a qHash() overload for std::pair. [ChangeLog][QtCore] Added qHash(std::pair), defined in <QHashFunctions>. Change-Id: I0f61c513e82e05ce9d2e56bcf18f3be9e2da4da9 Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>
* Split qHash()-related code into separate headerMarc Mutz2015-04-081-0/+156
The reduces the amount of code the compiler has to parse when all the header does is implement its own qHash(). I left the implementation in qhash.cpp, as it doesn't influence qHash*() users. Change-Id: Id320d690a33769bae78b03ccc3b08f7124123459 Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com> Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
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