Difference between functions and properties in Vala

Question

New to Vala here... trying to understand the difference between properties and getters/setters.

public class Person {
  public string name {
    get {
      XPath.NodeSet* nodes = search (node, "/name");
      return nodes->item (0)->get_content (); 
    }
  }

  public string get_name() {
    XPath.NodeSet* nodes = search (node, "/name");
    return nodes->item (0)->get_content (); 
  }
}

The second get_name () function works as expected. The property does not. It throws:

Return value transfers ownership but function return type hasn't been declared to transfer ownership
      return nodes->item (0)->get_content (); 
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

What am I missing here? Is the get_content () not returning a string or does the function solution do some conversion magic?

Thanks!

Answer 1

Normally, functions return owned values (caller must free), but property getters return unowned values (caller must not free). So, the memory returned by get_context () will be deallocated and a dangling pointer returned. The values properties return need to either be backed by values that are owned elsewhere (e.g., in a field) or change the return type to be owned so Vala will make a copy of the value.