Thoughts on IEEE P754

David-Sarah Hopwood david.hopwood at
Fri Aug 22 12:42:48 PDT 2008

David Jones wrote:
> On 22 Aug 2008, at 19:28, David-Sarah Hopwood wrote:
>> Two values that are === should index the same property [*].
>> [*] but not conversely: two values that index the same property are
>>      not necessarily ===.
> That highly desirable, but not true, as my earlier message illustrates.  
> In ES3 the ToString operator on Numbers is not required to be a true 
> function in the sense of always yielding the same result for the same 
> input.

That's true, but I strongly believe that it is a specification bug that
should be fixed for ES3.1 and ES-Harmony.

In practice, AFAIK, all the common JavaScript implementations do have a
deterministic ToString operation on numbers (that is, deterministic for
each implementation; I don't know whether there are differences between

# In order to ensure implementations all behave the same way I suggest
# the note at end of section 9.8.1 be moved to normative status.

I agree.

David-Sarah Hopwood

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