This method has three variants:
*:int EvalString (const char *, const class AttrList *, char *)
*:int EvalString (const char *, const class AttrList *, char **value)
*:int EvalString (const char *, const class AttrList *, MyString & value)

New {quote:ClassAds} already have a compatibility version of the first variant. Writing compatibility methods for the other two will be easy.

Developer time: 1 hour