1 files changed, 256 insertions, 0 deletions
diff --git a/src/corelib/doc/snippets/code/src_corelib_tools_qmultimap.cpp b/src/corelib/doc/snippets/code/src_corelib_tools_qmultimap.cpp
new file mode 100644
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+++ b/src/corelib/doc/snippets/code/src_corelib_tools_qmultimap.cpp
@@ -0,0 +1,256 @@
+// Copyright (C) 2020 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+//! [0]
+QMultiMap<QString, int> multimap;
+//! [0]
+
+
+//! [2]
+multimap.insert("a", 1);
+multimap.insert("b", 3);
+multimap.insert("c", 7);
+multimap.insert("c", -5);
+//! [2]
+
+
+//! [3]
+int num2 = multimap.value("a"); // 1
+int num3 = multimap.value("thirteen"); // not found; 0
+int num3 = 0;
+auto it = multimap.constFind("b");
+if (it != multimap.cend()) {
+    num3 = it.value();
+}
+//! [3]
+
+
+//! [4]
+int timeout = 30;
+if (multimap.contains("TIMEOUT"))
+    timeout = multimap.value("TIMEOUT");
+
+// better:
+auto it = multimap.find("TIMEOUT");
+if (it != multimap.end())
+    timeout = it.value();
+//! [4]
+
+
+//! [5]
+int timeout = multimap.value("TIMEOUT", 30);
+//! [5]
+
+
+//! [7]
+QMultiMapIterator<QString, int> i(multimap);
+while (i.hasNext()) {
+    i.next();
+    cout << qPrintable(i.key()) << ": " << i.value() << endl;
+}
+//! [7]
+
+
+//! [8]
+for (auto i = multimap.cbegin(), end = multimap.cend(); i != end; ++i)
+    cout << qPrintable(i.key()) << ": " << i.value() << endl;
+//! [8]
+
+
+//! [9]
+multimap.insert("plenty", 100);
+multimap.insert("plenty", 2000);
+// multimap.size() == 2
+//! [9]
+
+
+//! [10]
+QList<int> values = multimap.values("plenty");
+for (auto i : std::as_const(values))
+    cout << i << endl;
+//! [10]
+
+
+//! [11]
+auto i = multimap.find("plenty");
+while (i != map.end() && i.key() == "plenty") {
+    cout << i.value() << endl;
+    ++i;
+}
+
+// better:
+auto [i, end] = multimap.equal_range("plenty");
+while (i != end) {
+    cout << i.value() << endl;
+    ++i;
+}
+//! [11]
+
+
+//! [12]
+QMap<QString, int> multimap;
+...
+for (int value : std::as_const(multimap))
+    cout << value << endl;
+//! [12]
+
+
+//! [13]
+#ifndef EMPLOYEE_H
+#define EMPLOYEE_H
+
+class Employee
+{
+public:
+    Employee() {}
+    Employee(const QString &name, QDate dateOfBirth);
+    ...
+
+private:
+    QString myName;
+    QDate myDateOfBirth;
+};
+
+inline bool operator<(const Employee &e1, const Employee &e2)
+{
+    if (e1.name() != e2.name())
+        return e1.name() < e2.name();
+    return e1.dateOfBirth() < e2.dateOfBirth();
+}
+
+#endif // EMPLOYEE_H
+//! [13]
+
+
+//! [15]
+QMultiMap<int, QString> multimap;
+multimap.insert(1, "one");
+multimap.insert(5, "five");
+multimap.insert(5, "five (2)");
+multimap.insert(10, "ten");
+
+multimap.lowerBound(0);      // returns iterator to (1, "one")
+multimap.lowerBound(1);      // returns iterator to (1, "one")
+multimap.lowerBound(2);      // returns iterator to (5, "five")
+multimap.lowerBound(5);      // returns iterator to (5, "five")
+multimap.lowerBound(6);      // returns iterator to (10, "ten")
+multimap.lowerBound(10);     // returns iterator to (10, "ten")
+multimap.lowerBound(999);    // returns end()
+//! [15]
+
+
+//! [16]
+QMap<QString, int> multimap;
+...
+QMap<QString, int>::const_iterator i = multimap.lowerBound("HDR");
+QMap<QString, int>::const_iterator upperBound = multimap.upperBound("HDR");
+while (i != upperBound) {
+    cout << i.value() << endl;
+    ++i;
+}
+//! [16]
+
+
+//! [17]
+QMultiMap<int, QString> multimap;
+multimap.insert(1, "one");
+multimap.insert(5, "five");
+multimap.insert(5, "five (2)");
+multimap.insert(10, "ten");
+
+multimap.upperBound(0);      // returns iterator to (1, "one")
+multimap.upperBound(1);      // returns iterator to (5, "five")
+multimap.upperBound(2);      // returns iterator to (5, "five")
+multimap.lowerBound(5);      // returns iterator to (5, "five (2)")
+multimap.lowerBound(6);      // returns iterator to (10, "ten")
+multimap.upperBound(10);     // returns end()
+multimap.upperBound(999);    // returns end()
+//! [17]
+
+//! [19]
+for (auto it = multimap.begin(), end = multimap.end(); i != end; ++i)
+    i.value() += 2;
+//! [19]
+
+void erase()
+{
+QMultiMap<QString, int> multimap;
+//! [20]
+QMultiMap<QString, int>::const_iterator i = multimap.cbegin();
+while (i != multimap.cend()) {
+    if (i.value() > 10)
+        i = multimap.erase(i);
+    else
+        ++i;
+}
+//! [20]
+//! [21]
+erase_if(multimap, [](const QMultiMap<QString, int>::iterator it) { return it.value() > 10; });
+//! [21]
+}
+
+
+//! [23]
+if (i.key() == "Hello")
+    i.value() = "Bonjour";
+//! [23]
+
+
+//! [24]
+QMultiMap<QString, int> multi;
+multimap.insert("January", 1);
+multimap.insert("February", 2);
+...
+multimap.insert("December", 12);
+
+for (auto i = multimap.cbegin(), end = multimap.cend(); i != end; ++i)
+    cout << qPrintable(i.key()) << ": " << i.value() << endl;
+//! [24]
+
+
+//! [25]
+QMultiMap<QString, int> map1, map2, map3;
+
+map1.insert("plenty", 100);
+map1.insert("plenty", 2000);
+// map1.size() == 2
+
+map2.insert("plenty", 5000);
+// map2.size() == 1
+
+map3 = map1 + map2;
+// map3.size() == 3
+//! [25]
+
+//! [keyiterator1]
+for (auto it = multimap.cbegin(), end = multimap.cend(); it != end; ++it) {
+    cout << "The key: " << it.key() << endl
+    cout << "The value: " << qPrintable(it.value()) << endl;
+    cout << "Also the value: " << qPrintable(*it) << endl;
+}
+//! [keyiterator1]
+
+//! [keyiterator2]
+// Inefficient, keys() is expensive
+QList<int> keys = multimap.keys();
+int numPrimes = std::count_if(multimap.cbegin(), multimap.cend(), isPrimeNumber);
+qDeleteAll(multimap2.keys());
+
+// Efficient, no memory allocation needed
+int numPrimes = std::count_if(multimap.keyBegin(), multimap.keyEnd(), isPrimeNumber);
+qDeleteAll(multimap2.keyBegin(), multimap2.keyEnd());
+//! [keyiterator2]
+
+//! [26]
+QMultiMap<QString, int> map;
+map.insert("January", 1);
+map.insert("February", 2);
+// ...
+map.insert("December", 12);
+
+for (auto [key, value] : map.asKeyValueRange()) {
+    cout << qPrintable(key) << ": " << value << endl;
+    --value; // convert to JS month indexing
+}
+//! [26]