> On Mar 23, 2020, at 8:14 AM, Sven Van Caekenberghe <s...@stfx.eu> wrote: > > Both are excellent suggestions. > > We have to think a bit about the consequences. > > Still, both would not solve the problem of what to return when the collection > is empty.
Zero? > >> On 23 Mar 2020, at 15:47, Konrad Hinsen <konrad.hin...@fastmail.net> wrote: >> >> Am 23.03.20 um 14:45 schrieb James Foster: >> >>>> On Mar 23, 2020, at 6:06 AM, Sven Van Caekenberghe <s...@stfx.eu> wrote: >>>> >>>> What you found out now is that the clever trick used to avoid picking an >>>> additive identity (picking an element, counting it twice and then >>>> subtracting it) leads to a loss of precision when floating point numbers >>>> are involved. This is an important issue. >>> If this approach is to be preserved, then each class should have an >>> additive identity so instead of adding and subtracting an object, we let >>> the object tell us its zero. >> >> Or define a singleton class "Zero" with a + method that returns the other >> operand, and use that Zero object for the additive identity. >> >> Konrad. >> >> > > >
