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Pijul – A free and open source distributed version control system

pijul.org

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Re: Pijul – A free and open source distributed version control system

#71

Post by falsedan »

lvh wrote: post #60
falsedan wrote: post #41

Earlier quoted context omitted.

This doesn't seem significantly different to git, from the perspective of a user. Under the hood, I model a git branch as a ref pointing to a commit object in a DAG. In the driver's seat (git log --patch branch..upstream), I think of it as an ordered collection of diffs.

In darcs or pijul there is no DAG; there is only a collection of patches. The ordering between them is implicit, computed on demand, and can change as a consequence of merges.

It sounds as this is mostly an internal difference. Certainly, the mental model you described can be used on git reasonably well, from the user's point of view, and they won't get steered too far off course with it.

Re: Pijul – A free and open source distributed version control system

#72

Post by kzrdude »

jdbernard wrote: post #68
lvh wrote: post #53

Earlier quoted context omitted.

Internally, git objects are snapshots -- the differences are computed on demand. That is a critical difference, because it has implications for how merging can work. For example: https://tahoe-lafs.org/~zooko/badmerge/simple.html Even when using git am or send-email or whatever, yes, you're sending a patch -- but the way to apply that patch is to turn it into a commit and then cherry pick or rebase or merge or manual…

So, I didn't believe you because my internal mental model of a git repo is a DAG of changesets. And indeed, that is a good way to think about it, because almost all of git's operations behave like this. Commit history is almost always presented to the user as a series of diffs. But, you are correct. Internally, git stores the full contents of files and computes the diffs on the fly. For others' benefit, if you want t…

That is the most basic storage format in git, but it has packfiles too where it uses deltas. But not necessarily changesets' diffs!

Re: Pijul – A free and open source distributed version control system

#74

Post by stestagg »

maxpert wrote: post #65

Is anyone using Darcs or Pijul at work?

I used darcs for a while a few years back, it was ok. But definitely less polished than git.

Also the only vcs I've ever used where the repo managed to corrupt itself to the point I lost committed but unpushed changes

Re: Pijul – A free and open source distributed version control system

#75

Post by OJFord »

cstrahan wrote: post #70
OJFord wrote: post #58

Earlier quoted context omitted.

I think you showed the opposite point - you've argued commutativity is intuitive, but certainly non-commutativity can be part of a mathematical model.

A simpler explanation to that of my sibling post -- your point is akin to this fallacy: Susan: My brother plays such great music with his violin! Bob: Actually, I think you're arguing the opposite point -- a violin has strings that can be mishandled such that they cause annoying screechy sounds, so surely he's capable of producing a cacophony of screechy sounds. Not so enjoyable. Susan: Okay... but he's a good musici…

I have no idea where we're going with this.

You're original argument was that mathematics can model things that we might arrive at intuitively, without looking at the model - such as assuming commutativity in package manager installation order - correct?

I'm simply saying that mathematics can also describe things which are surprising; counter-intuitive even, so I agree with 'higher' comments in that being:

> based on a mathematical model of collaborative edition

is not sufficient for having that:

> behavior matches intution, [sic] every time

It just doesn't follow. Not least because one man's intuition differs from another's.

Re: Pijul – A free and open source distributed version control system

#76

Post by donpdonp »

Is there any new status on this project?

The last blog post from 2017-Jan-10 says "I’m pleased to announce that we are starting to test the first usable version of Pijul.We are not quite ready to release.."

I was hoping that getting to the front page meant pijul had done a release but I see nothing to that effect.

Re: Pijul – A free and open source distributed version control system

#77

Post by stormbrew »

scotu wrote: post #17
zellyn wrote: post #10

Sadly, I'm afraid the AGPL license is going to make this untouchable to businesses… :-( [Edit] Interestingly, they cover that. I suppose if you're just running Pijul rather than integrating with its code, it might be safe to use in a corporate environment. Still, it's likely to be offputting.

Why do you find it offputting? IANAL but it basically doesn't allow you to add code to (or get code from) Pijul itself and making it in another license. You can use it to store closed source code, you can host it yourself, offer it as a sevice for money, you can even create your own extensions as long as you release them AGPL... I feel that AGPL for a product is misunderstood and pre-rejected without justification by…

Here's the thing: Lawyers are expensive and legal implications are often not obvious to non-lawyers. Without a really really compelling reason to invoke them to clear the use of an AGPL project, clearing the use of it as non-threatening to the business' distribution model is probably not worth it. This is why businesses ban it outright.

Re: Pijul – A free and open source distributed version control system

#78

Post by Jach »

mhd wrote: post #26

"Because Pijul is based on a mathematical model of collaborative edition, its behavior matches intution, every time." That's not how math and/or intuition works.

Also supposing it were, git is also mathemagically intuitive when you view commits as isomorphic contours in source-code phase space (http://tartley.com/?p=1267) thus mathematical foundations are not enough to distinguish Pijul.

Re: Pijul – A free and open source distributed version control system

#79

Post by frant-hartm »

scotu wrote: post #17
zellyn wrote: post #10

Sadly, I'm afraid the AGPL license is going to make this untouchable to businesses… :-( [Edit] Interestingly, they cover that. I suppose if you're just running Pijul rather than integrating with its code, it might be safe to use in a corporate environment. Still, it's likely to be offputting.

Why do you find it offputting? IANAL but it basically doesn't allow you to add code to (or get code from) Pijul itself and making it in another license. You can use it to store closed source code, you can host it yourself, offer it as a sevice for money, you can even create your own extensions as long as you release them AGPL... I feel that AGPL for a product is misunderstood and pre-rejected without justification by…

> offer it as a sevice for money

Yes, you can, but if you add something - like issue tracking, user/access management etc.. around that then you need to publish that under AGPL as well..

It means it will never be part of something like github, bitbucket or AWS CodeCommit.

And then there are plugins to CIs (checkout from repository ...) - would those be affected?

Re: Pijul – A free and open source distributed version control system

#80

Post by kibwen »

mirekrusin wrote: post #16
zellyn wrote: post #10

Sadly, I'm afraid the AGPL license is going to make this untouchable to businesses… :-( [Edit] Interestingly, they cover that. I suppose if you're just running Pijul rather than integrating with its code, it might be safe to use in a corporate environment. Still, it's likely to be offputting.

I may be wrong but I think some (most? all?) companies that are blacklisting agpl3 won't bother going into small print details, license alone is a no-go, no?

Any company blacklisting AGPL is going to be blacklisting GPL as well, which would preclude using git as well (even the more permissive libgit2 is just GPL with a linking exception).
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