Add front()/back() to QString, QStringRef, QByteArray and QLatin1String

These STL-compatibility functions are present on our generic
containers, but not on the string classes.

[ChangeLog][QtCore][QString/QStringRef/QByteArray/QLatin1String] Added
front() and back() for STL compatibility.

Change-Id: I536019396b319abd1e2daf9c64ebab4e7a35b334
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 60 insertions, 0 deletions

diff --git a/src/corelib/tools/qbytearray.cpp b/src/corelib/tools/qbytearray.cpp
index 329cc358d4..6be28fea5f 100644
--- a/src/corelib/tools/qbytearray.cpp
+++ b/src/corelib/tools/qbytearray.cpp
@@ -1446,6 +1446,66 @@ QByteArray &QByteArray::operator=(const char *str)
     \overload
 */
 
+/*!
+    \fn char QByteArray::front() const
+    \since 5.10
+
+    Returns the first character in the byte array.
+    Same as \c{at(0)}.
+
+    This function is provided for STL compatibility.
+
+    \warning Calling this function on an empty byte array constitutes
+    undefined behavior.
+
+    \sa back(), at(), operator[]()
+*/
+
+/*!
+    \fn char QByteArray::back() const
+    \since 5.10
+
+    Returns the last character in the byte array.
+    Same as \c{at(size() - 1)}.
+
+    This function is provided for STL compatibility.
+
+    \warning Calling this function on an empty byte array constitutes
+    undefined behavior.
+
+    \sa front(), at(), operator[]()
+*/
+
+/*!
+    \fn QByteRef QByteArray::front()
+    \since 5.10
+
+    Returns a reference to the first character in the byte array.
+    Same as \c{operator[](0)}.
+
+    This function is provided for STL compatibility.
+
+    \warning Calling this function on an empty byte array constitutes
+    undefined behavior.
+
+    \sa back(), at(), operator[]()
+*/
+
+/*!
+    \fn QByteRef QByteArray::back()
+    \since 5.10
+
+    Returns a reference to the last character in the byte array.
+    Same as \c{operator[](size() - 1)}.
+
+    This function is provided for STL compatibility.
+
+    \warning Calling this function on an empty byte array constitutes
+    undefined behavior.
+
+    \sa front(), at(), operator[]()
+*/
+
 /*! \fn bool QByteArray::contains(const QByteArray &ba) const
 
     Returns \c true if the byte array contains an occurrence of the byte