When a+b+c does not equal c+b+a

Re:When a+b+c does not equal c+b+a by DannoHung on Friday June 05, 2015 @09:40AM (#9665407)

Is it really overloading that's the problem here? Even if you used method names to do this, you'd still have to deal with the fact that the operation being performed is non-commutative.

I don't know that there is a way of expressing such a restriction even if you were using dependent types in such a way as to prevent shooting yourself in the foot here. Possibly you could not implement the month or year span elements altogether and only allow addition of days or seconds?

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Re:When a+b+c does not equal c+b+a by erdeszt on Friday June 05, 2015 @12:57PM (#9666554)

But nested method calls don't imply commutativity while addition does. So the code is misleading.

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Re:When a+b+c does not equal c+b+a by DannoHung on Friday June 05, 2015 @02:14PM (#9667035)

I don't follow. How do nested method calls fail to imply commutativity?

For example, using psuedo-Haskell notation:

    (+):: Int -> Int -> Int

    ; ncc short for non commutative combination
    ncc:: Time -> Time -> Time

    1 + 2 + 3

    ncc 03:00 (ncc 10:00 02:00)

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Re:When a+b+c does not equal c+b+a by erdeszt on Friday June 05, 2015 @04:24PM (#9667887)

It could be just me but I would expect something that looks like an addition to be commutative but not arbitrary function calls. But I see what you mean that the types are not much of a help here.

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