Doc: Qt Concurrent: Link to essential usage information

Functions under the QtConcurrent namespace used to be documented
as header files, using the \headerfile command. These documents
have been since converted to standard pages using the \page
command, and the reference documentation for these functions
now live in the namespace page only.

However, the former pages contain useful usage information and
code snippets, but they've not been linked to from anywhere.

This change links to these pages from the module landing page,
as well as from the function reference doc.

Change-Id: Ia750d72d12503cec96ee2c9e202dd561e548cb24
Task-number: QTBUG-28977
Reviewed-by: Venugopal Shivashankar <venugopal.shivashankar@digia.com>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@theqtcompany.com>
Reviewed-by: Sze Howe Koh <szehowe.koh@gmail.com>

1 files changed, 28 insertions, 19 deletions

diff --git a/src/concurrent/doc/src/qtconcurrent-index.qdoc b/src/concurrent/doc/src/qtconcurrent-index.qdoc
index 2157280021..e57ebd2424 100644
--- a/src/concurrent/doc/src/qtconcurrent-index.qdoc
+++ b/src/concurrent/doc/src/qtconcurrent-index.qdoc
@@ -49,26 +49,35 @@
     applications:
 
     \list
+    \li \l {Concurrent Map and Map-Reduce}
+        \list
+            \li \l {QtConcurrent::map}{QtConcurrent::map()} applies a function
+                to every item in a container, modifying the items in-place.
+            \li \l {QtConcurrent::mapped}{QtConcurrent::mapped()} is like
+                map(), except that it returns a new container with the
+                modifications.
+            \li \l {QtConcurrent::mappedReduced}{QtConcurrent::mappedReduced()}
+                is like mapped(), except that the modified results are reduced
+                or folded into a single result.
+        \endlist
+
+    \li \l {Concurrent Filter and Filter-Reduce}
+    \list
+        \li \l {QtConcurrent::filter}{QtConcurrent::filter()} removes all items
+            from a container based on the result of a filter function.
+        \li \l {QtConcurrent::filtered}{QtConcurrent::filtered()} is like
+            filter(), except that it returns a new container with the filtered
+            results.
+        \li \l {QtConcurrent::filteredReduced}{QtConcurrent::filteredReduced()}
+            is like filtered(), except that the filtered results are reduced or
+            folded into a single result.
+    \endlist
 
-    \li \l {QtConcurrent::map}{QtConcurrent::map()} applies a function to every item in a container,
-    modifying the items in-place.
-
-    \li \l {QtConcurrent::mapped}{QtConcurrent::mapped()} is like map(), except that it returns a new
-    container with the modifications.
-
-    \li \l {QtConcurrent::mappedReduced}{QtConcurrent::mappedReduced()} is like mapped(), except that the
-    modified results are reduced or folded into a single result.
-
-    \li \l {QtConcurrent::filter}{QtConcurrent::filter()} removes all items from a container based on the
-    result of a filter function.
-
-    \li \l {QtConcurrent::filtered}{QtConcurrent::filtered()} is like filter(), except that it returns a new
-    container with the filtered results.
-
-    \li \l {QtConcurrent::filteredReduced}{QtConcurrent::filteredReduced()} is like filtered(), except that the
-    filtered results are reduced or folded into a single result.
-
-    \li \l {QtConcurrent::run}{QtConcurrent::run()} runs a function in another thread.
+    \li \l {Concurrent Run}
+    \list
+        \li \l {QtConcurrent::run}{QtConcurrent::run()} runs a function in
+            another thread.
+    \endlist
 
     \li QFuture represents the result of an asynchronous computation.