QtCore: replace 0 with \nullptr in documentation

Replace 0 with \nullptr in the documentation.
As a drive-by also replace some 0 with nullptr in the corresponding
code.

Change-Id: I101a61f5fad71cadb73bba9a8fd5dce6cc0836d0
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

3 files changed, 13 insertions, 11 deletions

diff --git a/src/corelib/statemachine/qabstractstate.cpp b/src/corelib/statemachine/qabstractstate.cpp
index 1a9ad4601d..0db44bc427 100644
--- a/src/corelib/statemachine/qabstractstate.cpp
+++ b/src/corelib/statemachine/qabstractstate.cpp
@@ -155,7 +155,8 @@ QAbstractState::~QAbstractState()
 }
 
 /*!
-  Returns this state's parent state, or 0 if the state has no parent state.
+  Returns this state's parent state, or \nullptr if the state has no
+  parent state.
 */
 QState *QAbstractState::parentState() const
 {
@@ -166,8 +167,8 @@ QState *QAbstractState::parentState() const
 }
 
 /*!
-  Returns the state machine that this state is part of, or 0 if the state is
-  not part of a state machine.
+  Returns the state machine that this state is part of, or \nullptr if
+  the state is not part of a state machine.
 */
 QStateMachine *QAbstractState::machine() const
 {
diff --git a/src/corelib/statemachine/qabstracttransition.cpp b/src/corelib/statemachine/qabstracttransition.cpp
index ebf33e120a..d841fd3c8b 100644
--- a/src/corelib/statemachine/qabstracttransition.cpp
+++ b/src/corelib/statemachine/qabstracttransition.cpp
@@ -195,8 +195,8 @@ QAbstractTransition::~QAbstractTransition()
 }
 
 /*!
-  Returns the source state of this transition, or 0 if this transition has no
-  source state.
+  Returns the source state of this transition, or \nullptr if this
+  transition has no source state.
 */
 QState *QAbstractTransition::sourceState() const
 {
@@ -205,14 +205,14 @@ QState *QAbstractTransition::sourceState() const
 }
 
 /*!
-  Returns the target state of this transition, or 0 if the transition has no
-  target.
+  Returns the target state of this transition, or \nullptr if the
+  transition has no target.
 */
 QAbstractState *QAbstractTransition::targetState() const
 {
     Q_D(const QAbstractTransition);
     if (d->targetStates.isEmpty())
-        return 0;
+        return nullptr;
     return d->targetStates.first().data();
 }
 
@@ -325,8 +325,8 @@ void QAbstractTransition::setTransitionType(TransitionType type)
 }
 
 /*!
-  Returns the state machine that this transition is part of, or 0 if the
-  transition is not part of a state machine.
+  Returns the state machine that this transition is part of, or
+  \nullptr if the transition is not part of a state machine.
 */
 QStateMachine *QAbstractTransition::machine() const
 {
diff --git a/src/corelib/statemachine/qstate.cpp b/src/corelib/statemachine/qstate.cpp
index 2531874a87..ae13d4e4cf 100644
--- a/src/corelib/statemachine/qstate.cpp
+++ b/src/corelib/statemachine/qstate.cpp
@@ -473,7 +473,8 @@ void QState::onExit(QEvent *event)
 }
 
 /*!
-  Returns this state's initial state, or 0 if the state has no initial state.
+  Returns this state's initial state, or \nullptr if the state has no
+  initial state.
 */
 QAbstractState *QState::initialState() const
 {