Hi,

I just stumbled across this bug related to the equality between fraction and float:

https://pharo.fogbugz.com/f/cases/20488/x-y-iff-x-y-0-is-not-preserved-in-Pharo

In essence, the problem can be seen that by doing this, you get a ZeroDivide:

x��:=��0.1.

y :=��(1/10).

x =��y ifFalse:��[��1��/��(x��-��y)��]

The issue seems to come from the Float being turned to a Fraction, rather than the Fraction being turned into a Float:

Fraction(Number)>>adaptToFloat: rcvr andCompare: selector��
"If I am involved in comparison with a Float, convert rcvr to a
Fraction. This way, no bit is lost and comparison is exact."

rcvr isFinite
ifFalse: [
selector == #= ifTrue: [^false].
selector == #~= ifTrue: [^true].
rcvr isNaN ifTrue: [^ false].
(selector = #< or: [selector = #'<='])
ifTrue: [^ rcvr positive not].
(selector = #> or: [selector = #'>='])
ifTrue: [^ rcvr positive].
^self error: 'unknow comparison selector'].

^ rcvr asTrueFraction perform: selector with: self

Even if the comment says that the comparison is exact, to me this is a bug because it seems to fail doing that. What do you think?

Cheers,

Doru

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