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-rw-r--r--src/corelib/doc/snippets/code/src_corelib_tools_qhash.cpp19
1 files changed, 19 insertions, 0 deletions
diff --git a/src/corelib/doc/snippets/code/src_corelib_tools_qhash.cpp b/src/corelib/doc/snippets/code/src_corelib_tools_qhash.cpp
index 43d64fc08e..0ac7cb5769 100644
--- a/src/corelib/doc/snippets/code/src_corelib_tools_qhash.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_tools_qhash.cpp
@@ -298,6 +298,25 @@ while (i != hash.end() && i.key() == "plenty") {
}
//! [26]
+//! [27]
+for (QHash<int, QString>::const_iterator it = hash.cbegin(), end = hash.cend(); it != end; ++it) {
+ cout << "The key: " << it.key() << endl
+ cout << "The value: " << it.value() << endl;
+ cout << "Also the value: " << (*it) << endl;
+}
+//! [27]
+
+//! [28]
+// Inefficient, keys() is expensive
+QList<int> keys = hash.keys();
+int numPrimes = std::count_if(keys.cbegin(), keys.cend(), isPrimeNumber);
+qDeleteAll(hash2.keys());
+
+// Efficient, no memory allocation needed
+int numPrimes = std::count_if(hash.keyBegin(), hash.keyEnd(), isPrimeNumber);
+qDeleteAll(hash2.keyBegin(), hash2.keyEnd());
+//! [28]
+
//! [qhashbits]
inline uint qHash(const std::vector<int> &key, uint seed = 0)
{