[darcs-users] domains: a proposal for composing repositories

[John Meacham]

On Wed, Feb 01, 2006 at 12:31:44AM +1030, Jonathon Mah wrote:
> then what happens to older patches? Can patches on the 'genutil'  
> domain now be applied to 'utilities'? Can new 'utilities' patches,  
> which operate on both Util/ and GenUtil.hs, be applied to  
> repositories that still contain the old domain layout?

domains don't affect patches at all. the only thing they do is change
the behavior of the darcs commands taking into account the current
content of the domain file at the moment record,push,pull,etc.. are
called. changing the domain file won't do anything to existing patches,
it will just make future record,push,pulls behave differently.

if you think of darcs commands as functions, like 

darcs record has a domain of file diffs and a codomain of patches
darcs changes has a domain of patches and a codomain of text descriptions
...

then the concept becomes clearer, domains simply restrict the domain of
various commands. they don't change the behavior of them at all, they
simply restrict the domain to some subset of the whole repo. in addition
to restricting the domains, it also ensures they are disjoint by making
sure (new) patches don't cross domain boundries.


        John

-- 
John Meacham - ⑆repetae.net⑆john⑈