clear_history -> clear_changes and some comments.

git-svn-id: svn://localhost/ardour2/branches/3.0@7685 d708f5d6-7413-0410-9779-e7cbd77b26cf

7 files changed, 30 insertions, 26 deletions

diff --git a/libs/pbd/pbd/properties.h b/libs/pbd/pbd/properties.h
index 41a5f74881..aeb0c3e069 100644
--- a/libs/pbd/pbd/properties.h
+++ b/libs/pbd/pbd/properties.h
@@ -88,7 +88,7 @@ public:
 		return _current;
 	}
 
-	void clear_history () {
+	void clear_changes () {
 		_have_old = false;
 	}
 
@@ -153,7 +153,7 @@ protected:
                                 if (v == _old) {
                                         /* value has been reset to the value
                                            at the start of a history transaction,
-                                           before clear_history() is called.
+                                           before clear_changes() is called.
                                            thus there is effectively no apparent
                                            history for this property.
                                         */
@@ -204,7 +204,7 @@ public:
                 }
         }
 
-        Property<T>* maybe_clone_self_if_found_in_history_node (const XMLNode& node) const {
+        Property<T>* clone_from_xml (const XMLNode& node) const {
 		XMLNodeList const & children = node.children ();
 		XMLNodeList::const_iterator i = children.begin();
 		while (i != children.end() && (*i)->name() != this->property_name()) {
diff --git a/libs/pbd/pbd/property_basics.h b/libs/pbd/pbd/property_basics.h
index f329916284..cfae36df20 100644
--- a/libs/pbd/pbd/property_basics.h
+++ b/libs/pbd/pbd/property_basics.h
@@ -90,21 +90,25 @@ public:
 
 	virtual PropertyBase* clone () const = 0;
         
-	/** Forget about any old value for this state */
-	virtual void clear_history () = 0;
+	/** Forget about any old changes to this property's value */
+	virtual void clear_changes () = 0;
 
 	/** Tell any things we own to forget about their old values */
-	virtual void clear_owned_history () {}
+	virtual void clear_owned_changes () {}
 
-        /** Get any changes in this property as XML and add it to a node */
+        /** Get any changes in this property as XML and add them to a node */
 	virtual void get_changes_as_xml (XMLNode *) const = 0;
 	
+        /** Get any changes in this property as Properties and add them to a list */
 	virtual void get_changes_as_properties (PropertyList& changes, Command *) const = 0;
 
 	/** Collect StatefulDiffCommands for changes to anything that we own */
 	virtual void rdiff (std::vector<StatefulDiffCommand*> &) const {}
-	
-        virtual PropertyBase* maybe_clone_self_if_found_in_history_node (const XMLNode&) const { return 0; }
+
+	/** Look in an XML node written by get_changes_as_xml and, if XML from this property
+	 *  is found, create a property with the changes from the XML.
+	 */
+        virtual PropertyBase* clone_from_xml (const XMLNode &) const { return 0; }
 
 	/** Set our value from an XML node.
 	 *  @return true if the value was set.
@@ -115,7 +119,7 @@ public:
 	virtual void get_value (XMLNode& node) const = 0;
 
 	/** @return true if this property has changed in value since construction or since
-	 *  the last call to clear_history(), whichever was more recent.
+	 *  the last call to clear_changes (), whichever was more recent.
 	 */
 	virtual bool changed() const = 0;
 
@@ -125,8 +129,8 @@ public:
 	/** Invert the changes in this property */
 	virtual void invert () = 0;
 
-	const gchar*property_name () const { return g_quark_to_string (_property_id); }
-	PropertyID  property_id () const   { return _property_id; }
+	const gchar* property_name () const { return g_quark_to_string (_property_id); }
+	PropertyID   property_id () const   { return _property_id; }
 
 	bool operator==(PropertyID pid) const {
 		return _property_id == pid;
diff --git a/libs/pbd/pbd/sequence_property.h b/libs/pbd/pbd/sequence_property.h
index 573bb4b539..7fdc964397 100644
--- a/libs/pbd/pbd/sequence_property.h
+++ b/libs/pbd/pbd/sequence_property.h
@@ -125,7 +125,7 @@ class SequenceProperty : public PropertyBase
 		return !_changes.added.empty() || !_changes.removed.empty();
 	}
 	
-	void clear_history () {
+	void clear_changes () {
 		_changes.added.clear ();
 		_changes.removed.clear ();
 	}
@@ -165,7 +165,7 @@ class SequenceProperty : public PropertyBase
 		}
         }
 
-	SequenceProperty<Container>* maybe_clone_self_if_found_in_history_node (XMLNode const & node) const {
+	SequenceProperty<Container>* clone_from_xml (XMLNode const & node) const {
 
 		XMLNodeList const children = node.children ();
 		
@@ -186,9 +186,9 @@ class SequenceProperty : public PropertyBase
 		return 0;
         }
 
-	void clear_owned_history () {
+	void clear_owned_changes () {
 		for (typename Container::iterator i = begin(); i != end(); ++i) {
-			(*i)->clear_history ();
+			(*i)->clear_changes ();
 		}
 	}
 
diff --git a/libs/pbd/pbd/stateful.h b/libs/pbd/pbd/stateful.h
index 050540dcd1..5c1f079bc6 100644
--- a/libs/pbd/pbd/stateful.h
+++ b/libs/pbd/pbd/stateful.h
@@ -67,8 +67,8 @@ class Stateful {
 
         /* history management */
 
-	void clear_history ();
-	virtual void clear_owned_history ();
+	void clear_changes ();
+	virtual void clear_owned_changes ();
         PropertyList* get_changes_as_properties (Command *) const;
 	virtual void rdiff (std::vector<StatefulDiffCommand*> &) const;
         bool changed() const;
diff --git a/libs/pbd/stateful.cc b/libs/pbd/stateful.cc
index 204e62685e..8411dc4e60 100644
--- a/libs/pbd/stateful.cc
+++ b/libs/pbd/stateful.cc
@@ -157,12 +157,12 @@ Stateful::instant_xml (const string& str, const sys::path& directory_path)
 	return 0;
 }
 
-/** Forget about any old state for this object */	
+/** Forget about any changes to this object's properties */
 void
-Stateful::clear_history ()
+Stateful::clear_changes ()
 {
 	for (OwnedPropertyList::iterator i = _properties->begin(); i != _properties->end(); ++i) {
-		i->second->clear_history ();
+		i->second->clear_changes ();
 	}
 }
 
@@ -329,7 +329,7 @@ Stateful::property_factory (const XMLNode& history_node) const
         PropertyList* prop_list = new PropertyList;
 
         for (OwnedPropertyList::const_iterator i = _properties->begin(); i != _properties->end(); ++i) {
-                PropertyBase* prop = i->second->maybe_clone_self_if_found_in_history_node (history_node);
+                PropertyBase* prop = i->second->clone_from_xml (history_node);
 
                 if (prop) {
                         prop_list->add (prop);
@@ -348,10 +348,10 @@ Stateful::rdiff (vector<StatefulDiffCommand*>& cmds) const
 }
 
 void
-Stateful::clear_owned_history ()
+Stateful::clear_owned_changes ()
 {
 	for (OwnedPropertyList::iterator i = _properties->begin(); i != _properties->end(); ++i) {
-		i->second->clear_owned_history ();
+		i->second->clear_owned_changes ();
 	}
 }
   
diff --git a/libs/pbd/stateful_diff_command.cc b/libs/pbd/stateful_diff_command.cc
index ffd56c8fb1..93a215ad8a 100644
--- a/libs/pbd/stateful_diff_command.cc
+++ b/libs/pbd/stateful_diff_command.cc
@@ -28,7 +28,7 @@ using namespace std;
 using namespace PBD;
 
 /** Create a new StatefulDiffCommand by examining the changes made to a Stateful
- *  since the last time that clear_history was called on it.
+ *  since the last time that clear_changes was called on it.
  *  @param s Stateful object.
  */
 
diff --git a/libs/pbd/test/scalar_properties.cc b/libs/pbd/test/scalar_properties.cc
index b637076cc6..cd736b14d3 100644
--- a/libs/pbd/test/scalar_properties.cc
+++ b/libs/pbd/test/scalar_properties.cc
@@ -29,7 +29,7 @@ ScalarPropertiesTest::testBasic ()
 	CPPUNIT_ASSERT (_fred == 4);
 	CPPUNIT_ASSERT (_fred.changed() == true);
 
-	_fred.clear_history ();
+	_fred.clear_changes ();
 	CPPUNIT_ASSERT (_fred.changed() == false);
 	
 	_fred = 5;