Questions about branching in Mercurial

[Marcin Kasperski]

> So let's say that we have one of these mega-repositories that contains  
> 150 branches.
> 
> That's potentially 150 heads in the repository.
> 
> In that case, what do expect to happen when you enter "hg merge"?

hg merge 
without params should perform the merge (if needed) on the current
branch. On which sill there is 1 head or two heads.

hg merge otherbranch
should merge that branch (equivalently to hg pull otherrepo; hg merge)

Even if there are 150 heads in repo, as long as I am on some branch,
heads defined within other branches matter only for those branches.

Not sure whether this model is easy to implement. But this is more or
less how one imagines branches...