Oops, forgot to copy the list
On Fri, Aug 22, 2008 at 6:54 PM, Sam Ruby <[EMAIL PROTECTED]> wrote: > On Fri, Aug 22, 2008 at 6:02 PM, Waldemar Horwat <[EMAIL PROTECTED]> wrote: >> Sam Ruby wrote: >>> On Fri, Aug 22, 2008 at 5:06 PM, Waldemar Horwat <[EMAIL PROTECTED]> wrote: >>>> Sam Ruby wrote: >>>>> On Fri, Aug 22, 2008 at 4:18 PM, Waldemar Horwat <[EMAIL PROTECTED]> >>>>> wrote: >>>>>> Sam Ruby wrote: >>>>>>> On Fri, Aug 22, 2008 at 3:55 PM, Waldemar Horwat <[EMAIL PROTECTED]> >>>>>>> wrote: >>>>>>>> Here's a question for you: >>>>>>>> >>>>>>>> What should the full result of converting 1.1 to a Decimal be in >>>>>>>> ECMAScript? Describe the precise answer and justify your choice of >>>>>>>> answer. Hint: This would behave remarkably differently depending on >>>>>>>> whether we settle on Decimal64 or Decimal128. >>>>>>> At the present time, I am only suggesting that ECMAScript support >>>>>>> Decimal128, and that there not by *any* implicit conversions to >>>>>>> Decimal. >>>>>>> >>>>>>> Decimal.parse(n) would take n.ToString() and then parse that as a >>>>>>> Decimal128 value. If (in the future) additional precisions were >>>>>>> allowed by the standard, then there would be a second parameter on >>>>>>> Decimal.parse that would allow the precision to be specified. >>>>>>> Meanwhile: >>>>>>> >>>>>>> true: Decimal.parse(1.1) == 1.1m >>>>>> An interesting choice. This produces more sensible results but directly >>>>>> violates IEEE P754 section 5.3.3. >>>>> I'm looking at DRAFT P754, April 24, 2008. Section 5.3.3 in this >>>>> draft is entitled "logBFormat operations". I doubt that's what you >>>>> are referring to. Can you provide me with a bit more context? >>>> Sorry, I meant 5.4.2. >>> >>> I still don't see the conflict. If we desire, we can provide multiple >>> mechanisms for converting binary64 floating point numbers to >>> decimal128 floating point numbers. At a minimum, we should provide an >>> analog to ES's existing parseFloat. I'd suggest that it be named >>> Decimal.parse instead, and that it make use of >>> decimal128-convertFromDecimalCharacter. >> >> Now we've gone full circle without actually answering the question I asked: >> What should the full result of converting 1.1 to a Decimal be in ECMAScript? >> >> "An error" or "you can't do it" is not a valid answer because it violates >> IEEE P754. > > I'm clearly not following something. > > I'm suggesting that there not be any implicit conversions from > binary64 to decimal128. I've made a suggestion as to what > Decimal.parse should do. If there are no other means to do a > conversion, that I can't answer the question about what such a > non-existent method might do. > > If you suggest that we need to do implicit conversions, I am aware of > a few different mechanisms to do so. I think that the one that > produces the most expected results would be based on > decimal128-convertFromDecimalCharacter. > > If we want to provide more explicit conversions, then such named > methods should match the definition in IEEE P754. > > I don't know how to more fully answer the question. > >> Waldemar >> _______________________________________________ >> Es-discuss mailing list >> [email protected] >> https://mail.mozilla.org/listinfo/es-discuss > > - Sam Ruby > _______________________________________________ Es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
