Add sections about std containers and algorithms

Add section comparing Qt containers and std containers.

Add snippets showing use of std algorithms with Qt containers.

Task-number: QTBUG-86584
Pick-to: 6.0
Change-Id: I1133a5214a5acd086c37658ca11ab205a19a489b
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

1 files changed, 21 insertions, 0 deletions

diff --git a/src/corelib/doc/snippets/code/doc_src_containers.cpp b/src/corelib/doc/snippets/code/doc_src_containers.cpp
index e5ccf0bb48..834056174f 100644
--- a/src/corelib/doc/snippets/code/doc_src_containers.cpp
+++ b/src/corelib/doc/snippets/code/doc_src_containers.cpp
@@ -319,3 +319,24 @@ QSet<int> set(list.begin(), list.end());
     Will generate a QSet containing 1, 2, 3, 4, 5.
 */
 //! [25]
+
+//! [26]
+QList<int> list { 2, 3, 1 };
+
+std::sort(list.begin(), list.end());
+/*
+    Sort the list, now contains { 1, 2, 3 }
+*/
+
+std::reverse(list.begin(), list.end());
+/*
+    Reverse the list, now contains { 3, 2, 1 }
+*/
+
+int even_elements =
+        std::count_if(list.begin(), list.end(), [](int element) { return (element % 2 == 0); });
+/*
+    Count how many elements that are even numbers, 1
+*/
+
+//! [26]