[darcs-devel] [issue772] bug in get_extra commuting patch

[zooko]

> The key mistake you're making is that you seem to assume that we could
> check this hash, but it's an uncheckable hash, because there's no  
> reason to
> believe we could ever again recreate that context.

This is what I meant by "theoretically could be used by a future  
version of darcs".  It is theoretically possible that a future  
version of darcs could get access to the context.

If in the future there were an extension to darcs to provide such  
contexts, then darcs would gain the same provenance guarantee that  
the other decentralized revision control tools offer without losing  
its unique flexibility.

Perhaps such an extension is too difficult to implement, but perhaps  
not.

>  So this information is
> no more useful than a truly random number.  Its only advantage over  
> a few
> bytes from /dev/random would be (a) that it doesn't deplete your  
> entropy
> pool

/dev/urandom suffices for that, and is no less secure than /dev/random.

> and (b) that tools like tailor would generate the same output when run
> twice on the same repository.

This would be a nice property for it to have.

> Sorry, it *would* be encoded into the long patch description  
> itself.  As
> I've explained to you before.  I'm not going to break
> backwards-compatibility.

I see.

Regards,

Zooko