(→External link: Mentioning David Roundy's slides ``Implementing the darcs patch formalism and verifying it'' (see also GADT#Projects containing GADTs article))
Revision as of 14:35, 22 August 2006
darcs is a peer-to-peer revision control system, written in Haskell.
1 Understanding darcs
You can think of a darcs repository as containing these things:
- Patches: a patch is a collection of changes that forms the unit of synchronisation with other repositories
- Unrecorded changes to known files and directories
- Unknown items (files and directories)
- Boring items: anything with a name matched in _darcs/prefs/boring
Note that some projects are keen on making sure all derivative items are "boring" rather than merely unknown items that will show up with darcs wh -l. Other projects less so.
2.1 Unknown items
- darcs whatsnew -l: show changes and unknown items
- creating a item: add item to the unknown items.
- darcs add: convert the unknown item into a change to create the item and its contents
- darcs remove: add a change to empty the item and delete it but keep it as an unknown item.
- darcs whatsnew: show unrecorded changes
- removing an item: add a change to remove the item
- editing a file: add a change for the edit
- darcs mv: add a change to move an item
- darcs replace: add a change to replace text in a file
- darcs record: record changes to add a patch
- darcs unrecord: remove a patch by turning back it into unrecorded changes
- darcs amend-record: replace a patch with one with added changes
- darcs revert: remove changes
- darcs changes: show patches
- darcs send --output=FILE: make an email bundle from patches
- darcs send --to=ADDRESS: send an email bundle from patches
- darcs pull: add patches from another repository
- darcs push: add patches from this repository to another repository
- darcs apply: add patches from an email bundle
- darcs rollback: add a patch that is the inverse of an existing patch
- darcs obliterate: remove a patch. Warning: if the patch doesn't exist elsewhere, you will lose that work.
- darcs tag: add a tag for the current set of patches
- darcs initialize: create a new empty repository
- darcs get: create a new empty repository and add patches from another repository
- Understanding darcs - an illustrated wikibook about darcs and patch theory
- Implementation details of
darcsshow motivating examples for generalised algebraic datatypes. The motivations are described in David Roundy's slides Implementing the darcs patch formalism and verifying it (see p. 11, 13--14.). The talk mentions also the notions of phantom type, and existential type, and type witness (see p. 15).