subroutinedigits_valuepure

pure subroutine digits_value(text, value, stat)
    character(len=*), intent(in) :: text    !! the digits
    integer, intent(out) :: value           !! their value
    integer, intent(out) :: stat            !! nonzero if there are none, or something else
    integer :: k

    value = 0
    stat = merge(1, 0, len(text) == 0)
    do k = 1, len(text)
        if (.not. is_digit(text(k:k))) then
            stat = 1
            return
        end if
        value = 10*value + iachar(text(k:k)) - iachar('0')
    end do
end subroutine digits_value