Recipes vs. Looms vs. pipelines

[James Westby]

On Tue Dec 15 16:54:14 +0000 2009 Aaron Bentley wrote:
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> James Westby wrote:
> > There are discussions about whether the "stack" model presented
> > by loom is the best, as it entagles threads that don't necessarily
> > have a dependency. There are alternative models proposed, including
> > a full DAG as implemented by TopGit. My fear is that they are
> > too complicated for people to easily grasp, and that they are
> > not the best way to solve the problems they aim to.
> 
> > Looms on the other hand currently have no parent pointers
> > per-thread.
> 
> If you want something that implements the stack model and provides
> parent pointers, we have that in bzr-pipeline.  It doesn't provide the
> same single-glob approach as loom, but that is mainly because bzr
> doesn't yet provide colocated branches.  We do want to add that support,
> so maybe now is a good time to do it.
> 
> > Looms are currently available in the bzr-loom plugin, but it
> > is generally agreed that this needs some polish to be really
> > usable.
> 
> bzr-pipeline is definitely already usable.  I use it daily, and it has
> other fans, like rockstar and thumper.  It is also under active development.
> 
> > Looms also allow for versioning at the loom level, as well
> > as at the revision level. This means that it is possible
> > to merge a loom as a whole, including operations that
> > add and delete threads. This is crucial to building a
> > packaging system on top of them.
> 
> These features are enbryonic in loom, and they could be added to
> bzr-pipeline.

Hi Aaron,

Thanks for bring up pipelines, I haven't investigated them sufficiently
before now.

I realise that there are other advantages, but choosing pipelines just
because they use real branches for the "threads," wouldn't be a wise
choice in my eyes. It's not something that can't fit in to the model
of looms, so we can always add it there.

Having said that, I would be wrong to dismiss pipelines without a fair
comparison, so let's do that.