Re: vcdiff generator status?

Jim Blandy wrote:
> I think you're confusing the true assertion:
>
> "Given a target string and a delta, you can't reconstruct the source string"
>
> with the false assertion:
>
> "Given a source string and a delta, you can't construct the inverse delta"

Ah, O.K., right. My bad.

> The latter is the situation I'm in. And I know I can do it: at the
> very worst, I could apply the delta to the source string to produce
> the target string and then run the delta algorithm again with the
> arguments reversed. However, I'm hoping that with fancy arithmetic I
> could do better.

In this case it should indeed be possible to invert the delta,
but I wonder if it's worhtwile. After all, you'll have to create
the target anyway (it'll mostly be the new tip of a branch, right?),
and I strongly suspect that reversing the delta would cost the
same as generating a new one.

    Brane

-- 
Branko Čibej                 <branko.cibej@hermes.si>
HERMES SoftLab, Litijska 51, 1000 Ljubljana, Slovenia
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