Type STObject helper functions, 'empty' and 'hasMatchingEntry'.

A small 'isFieldAllowed' bugfix.

src/SerializedObject.cpp

@@ -206,6 +206,8 @@ bool STObject::isValidForType()
 
 bool STObject::isFieldAllowed(SField::ref field)
 {
+	if (isFree())
+		return true;
 	BOOST_FOREACH(SOElement::ptr elem, mType)
 	{ // are any required elemnents missing
 		if (elem->e_field == field)
@@ -242,6 +244,14 @@ std::auto_ptr<SerializedType> STObject::deserialize(SerializerIterator& sit, SFi
 	return object;
 }
 
+bool STObject::hasMatchingEntry(const SerializedType& t)
+{
+	const SerializedType* o = peekAtPField(t.getFName());
+	if (!o)
+		return false;
+	return t == *o;
+}
+
 std::string STObject::getFullText() const
 {
 	std::string ret;

src/SerializedObject.h

@@ -156,6 +156,9 @@ public:
 	iterator end()					{ return mData.end(); }
 	const_iterator begin() const	{ return mData.begin(); }
 	const_iterator end() const		{ return mData.end(); }
+	bool empty() const				{ return mData.empty(); }
+
+	bool hasMatchingEntry(const SerializedType&);
 
 	bool operator==(const STObject& o) const;
 	bool operator!=(const STObject& o) const { return ! (*this == o); }