anchor.diff:      class(typeListDScal),intent(inout)::this !< this ListDScal
       
       this%len=0
  -    if(allocated(this%dat))then
  -      deallocate(this%dat)
  -    end if
  +    if(allocated(this%dat)) deallocate(this%dat)
     end subroutine
     
     !> extend this ListDScal by doubling size of dat or add n spaces
  
positive.code:     else
        allocate(newDat(max(1,(m*2))))
      end if
      if(m>0)then
        newDat(1:m)=this%dat(:)
      end if
      call move_alloc(newDat,this%dat)
    end subroutine
    
  
negative.code:     class(typeListIScal),intent(inout)::this
      
      this%len=0
      if(allocated(this%dat)) deallocate(this%dat)
    end subroutine
    
    !> extend this ListIScal by doubling size of dat or add n spaces
  