var a,b: MatrixInt; bvec: TMtxInt; begin a := MatrixInt.Create(true); //create from object cache via CreateIt //this constructor can be omitted, because it is implicitly called //the first time that the variable is used. //However: b := MatrixInt.Create(10); //Similar to bvec := TMtxInt.Create; try bvec.Size(10); finally bvec.Free; //b is freed on the exit from the procedure end; end;