The Inc and Dec procedures are – for optimization purposes – compiler intrinsics. They can be overridden in the usual manner by declaring a procedure:
procedure Inc(var s : String); begin Inc(S,'.'); end; procedure Inc(var s : String; T : String); begin S:=S+T; end;
But because they are compiler intrinsics, they can also be implemented as operators for custom types:
operator Inc (s,T : String) : z : string; begin Z:=S+T; end;