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Comment by gcb0 | Hacker News Reader

> patches are associative: pulling B and C together after A does the same as pulling just C after pulling A and B

that makes no sense to me. DARCS also claim this, but if you have the patches all changing the first line to a different value, obviously the last one will dictate the final value of the first line. Which is the same as git. in what world do you want to change orders of patches and not have the final state change?

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Associativity is not about changing the order but about a different grouping:

    ( A B ) C = A ( B C )

If A, B and C are patches, you are applying C last on the left side and A last on the right.

You are wrong. Yes, on the left side B is applied to A, then C is applied to the result (AB). However, on the right side, C is applied to B, then the result (BC) is applied to A. A is still the left most patch in both cases. BC could depend on (the output context of) A so it wouldn't make sense to apply A to BC! BC is applied to A. A(BC)

So you are saying that applying patches is not commutative? I was assuming A(BC) == (BC)A. What makes you think that the result should be different depending on the order?

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