>> > [...] and if you write 1.3, the object that represents that number
>> > is not going to be an instance of float but of scaledecimal or
>> > fraction or whatever, but not float...
>>
>> That only solves the issue of representing literals because:
>>
>>
>> > and all operations are made with exact representation.
>>
>>
>>
>> cannot be done for all operations: obvious ones like square root, log,
>> sin, etc and less obvious ones like #squared where you run out of
>> enough bits to maintain precision (in fixed-width implementations).
>
> not really... root, log, sin, etc could be messages that only inexact
> numbers know how to answer , so you want "2 sqrt",� do "2 asFloat sqrt", but
> for +, *, /, etc. they work as expected.
> We can also have better representations for number like pi. Why pi is
> instance of Float and not Pi? If pi is instance of Pi, then cos(pi/2) = 0
> could be true... just a quick hack:
> Pi>>/ aNumber
>
> � ^ Fraction numerator: self denominator: aNumber� "Or maybe an object
> representing that Pi has been divided/multiplied, etc
>
> Fraction>>cos
>
> �^ numerator cosDividedWith: denominator
>
> Pi>>cosDividedWith: denominator
>
> �^denominator = 2 ifTrue: [ 0 ] ifFalse: [ ... ]
>
> and so on
>
don't forget to add
Pi>>mantisOfLength: numBits
to compute the Pi up to given precision. :)
But your examples is not about computing a result, but rather predicting it.
So why bother writing so much stuff , while you can just implement :
Number>>cosPiHalved
�^ 0
:)
--
Best regards,
Igor Stasenko AKA sig.
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