+void Track::set_block(Block *b)
+{
+ if(b && !b->has_track(*this))
+ throw InvalidParameterValue("Track is not in the Block");
+ if(!b && block && block->has_track(*this))
+ throw InvalidState("Track is still in a Block");
+
+ block = b;
+}
+
+Block &Track::get_block() const
+{
+ if(!block)
+ throw InvalidState("No Block");
+
+ return *block;
+}
+