The existing API of QFlatMap did not allow efficient removal of
elements:
- std::remove_if does not apply, because it works by moving elements
back in the range onto those that need to be removed, which doesn't
work in flat_map's case, because, like for all associative
containers, the key in value_type is const.
- The node-based erase-loop (over it = cond ? c.erase(it) :
std::next(it)) works, but, unlike in traditional associative
containers, is quadratic, because flat_map::erase is a linear
operation.
According to Stepanov's principle of Efficient Computational Basis
(Elements of Programming, Section 1.4), we're therefore missing API.
Add it.
I couldn't make up my mind about the calling convention for the
predicate and, despite having authored a merged paper about erase_if,
can never remember what the predicate is supposed to take, so be fancy
and accept all: (*it), (it.key(), it.value()), (it.key()). This means
that unary predicates can either not be generic or must be properly
constrained to distinguish between pair<const K, V> and K, but that's
not necessarily a bad thing.
There's no reason to supply a Qt-ified removeIf on top of the standard
name, because this is private API and doubling the names would do
nothing except double the testing overhead.
Fixes: QTBUG-100983
Change-Id: I12545058958fc5d620baa770f92193c8de8b2d26
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
... which implements or assumes something about the
broken^Wnon-STL-compliant insertion behavior.
Once this has integrated into all module dependencies, we can
re-implement these APIs using STL-compatible semantics.
Task-number: QTBUG-100092
Change-Id: I54f4f5ce7addd9543866d2c399f48aff50983b88
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Add a level of indirection via void_t such that
struct is_transparent {};
works, and not just
using is_transparent = <unspecified>;
Pick-to: 6.3
Change-Id: I3ca2af6a07e6989dc95abc10fb2d0078a5269e5b
Reviewed-by: Jörg Bornemann <joerg.bornemann@qt.io>
This does exactly what insert() on Qt associative containers does, but
allows to express the intent of using the STL-incompatible Qt insert()
semantics, in an STL-compatible way, instead of leaving the reader of
the code wondering what semantics are expected.
This is part of a very-long-term goal of fixing Qt associative
container's insert() behavior, in which QFlatMap, being an affected,
but private-API type, is used for proof-of-concept purposes.
Task-number: QTBUG-99651
Pick-to: 6.3 6.2
Change-Id: I69010285438259918aef659d3235180c1b5be696
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
... in an attempt to foster the use of this data structure by making
it less onerous to spell.
Pick-to: 6.3 6.2
Change-Id: Ib9d17029c75278edde6ba90f65f68af179a6d230
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
QFlatMap, like its public brethren, features the broken Qt-style
insert() behavior (what the STL calls insert_or_assign()), which
makes its insert() unusable for actual STL-style insert() work,
with no replacement except the size-check-and-index-operator trick:
const auto oldSize = c.size();
auto &e = c[key];
if (c.size() != oldSize) {
// inserted
}
Even though QFlatMap::insert() appears to return the correct info,
it's useless, because the old value has been assigned over by the
time insert() returns.
Pick-to: 6.3 6.2
Change-Id: If4173c42523a128dfd22ab496dde0089ba73f41c
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
Remove the qmake project files for most of Qt.
Leave the qmake project files for examples, because we still test those
in the CI to ensure qmake does not regress.
Also leave the qmake project files for utils and other minor parts that
lack CMake project files.
Task-number: QTBUG-88742
Change-Id: I6cdf059e6204816f617f9624f3ea9822703f73cc
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Kai Koehne <kai.koehne@qt.io>
Complete search and replace of QtTest and QtTest/QtTest with QTest, as
QtTest includes the whole module. Replace all such instances with
correct header includes. See Jira task for more discussion.
Fixes: QTBUG-88831
Change-Id: I981cfae18a1cabcabcabee376016b086d9d01f44
Pick-to: 6.0
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Modify special case locations to use the new API as well.
Clean up some stale .prev files that are not needed anymore.
Clean up some project files that are not used anymore.
Task-number: QTBUG-86815
Change-Id: I9947da921f98686023c6bb053dfcc101851276b5
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Also removed add_subdirectory calls for subdirs which no longer exist.
Change-Id: I759f408ca812e1721dde495b0e23feffdeeb9c60
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
Add a light-weight associative container, API-wise very similar to QMap,
that's based on two sorted continuous containers (QVector by default).
The class is internal for now.
Change-Id: Ife12576c4abb39a3ea2acb0a1ba0faca91b3a4c5
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
