Difference between revisions of "Darcs"

Revision as of 18:21, 24 October 2013

darcs is a peer-to-peer revision control system, written in Haskell. It is the standard RCS of the Haskell community.

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
Unmanaged items (files and directories)
Boring items: anything with a name matched in _darcs/prefs/boring
The unrevert cache of changes

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.

Operations

Unmanaged items

darcs whatsnew -l: show changes to managed files, and unmanaged items

creating a item: add item to the unmanaged items.

darcs add: convert the unmanaged item into a change to create the item and its contents

darcs remove: add a change which empties the item and deletes it, but keep it as an unmanaged item.

Changes

darcs whatsnew: show unrecorded changes

removing a managed item: add a change to remove the item

editing a managed 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 and put them in the unrevert cache. Warning: you will lose the previous contents of the unrevert cache.

darcs unrevert: take changes out of the unrevert cache and add them to the unrecorded changes.

Patches

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

Repositories

darcs initialize: create a new empty repository

darcs get: create a new empty repository and add patches from another repository

External links

darcs
darcsden/darcs hub free darcs repository hosting
Understanding darcs - an illustrated wikibook about darcs and patch theory
Darcs, Taking version control to the next level, a tutorial
Benefits from a real world switch from CVS to darcs
Implementation details of darcs show 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).
See also other talks on darcs. One of them ([cufp.galois.com/2005/slides/DavidRoundy.pdf The Myth and Reality of using Haskell in the ‘Real World’]) discusses a more general topic: usefulness of Haskell (in real life) and in general, the power of (lazy) functional programming.
Conflict bug -(a problem in Darcs-1)
Another free darcs hosting (for open source projects) at patch-tag.com

@@ Line 1: / Line 1: @@
-'''darcs''' is a peer-to-peer revision control system, written in Haskell.
+'''darcs''' is a peer-to-peer revision control system, written in Haskell. It is the standard RCS of the Haskell community.
 == Understanding darcs ==
@@ Line 7: / Line 7: @@
 * '''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)
+* '''Unmanaged items''' (files and directories)
 * '''Boring items''': anything with a name matched in <tt>_darcs/prefs/boring</tt>
+* The '''unrevert cache''' of changes
 Note that some projects are keen on making sure all derivative items are "boring" rather than merely unknown items that will show up with <tt>darcs wh -l</tt>. Other projects less so.
@@ Line 14: / Line 15: @@
 == Operations ==
-=== Unknown items ===
+=== Unmanaged items ===
-*<tt>darcs whatsnew -l</tt>: show changes and unknown items
+*<tt>darcs whatsnew -l</tt>: show changes to managed files, and unmanaged items
-*'''creating a item''': add item to the unknown items.
+*'''creating a item''': add item to the unmanaged items.
-*<tt>darcs add</tt>: convert the unknown item into a change to create the item and its contents
+*<tt>darcs add</tt>: convert the unmanaged item into a change to create the item and its contents
-*<tt>darcs remove</tt>: add a change to empty the item and delete it but keep it as an unknown item.
+*<tt>darcs remove</tt>: add a change which empties the item and deletes it, but keep it as an unmanaged item.
 === Changes ===
@@ Line 28: / Line 29: @@
 *<tt>darcs whatsnew</tt>: show unrecorded changes
-*'''removing an item''': add a change to remove the item
+*'''removing a managed item''': add a change to remove the item
-*'''editing a file''': add a change for the edit
+*'''editing a managed file''': add a change for the edit
 *<tt>darcs mv</tt>: add a change to move an item
@@ Line 41: / Line 42: @@
 *<tt>darcs amend-record</tt>: replace a patch with one with added changes
+*<tt>darcs revert</tt>: remove changes and put them in the unrevert cache. ''Warning: you will lose the previous contents of the unrevert cache.''
+*<tt>darcs unrevert</tt>: take changes out of the unrevert cache and add them to the unrecorded changes.
 === Patches ===
@@ Line 46: / Line 51: @@
 *<tt>darcs changes</tt>: show patches
-*<tt>darcs send</tt>: make an email bundle from patches, and optionally send it
+*<tt>darcs send --output=''FILE''</tt>: make an email bundle from patches
+*<tt>darcs send --to=''ADDRESS''</tt>: send an email bundle from patches
 *<tt>darcs pull</tt>: add patches from another repository
@@ Line 57: / Line 64: @@
 *<tt>darcs obliterate</tt>: remove a patch. ''Warning: if the patch doesn't exist elsewhere, you will lose that work.''
+*<tt>darcs tag</tt>: add a tag for the current set of patches
 === Repositories ===
@@ Line 64: / Line 73: @@
 *<tt>darcs get</tt>: create a new empty repository and add patches from another repository
-== External link ==
+== External links ==
 * [http://darcs.net/ darcs]
+* [http://hub.darcs.net darcsden/darcs hub] free darcs repository hosting
+* [http://en.wikibooks.org/wiki/Understanding_darcs Understanding darcs] - an illustrated wikibook about darcs and patch theory
+* [http://blog.interlinked.org/tutorials/darcs.html Darcs, Taking version control to the next level], a tutorial
+* [http://mark.stosberg.com/blog/2005/01/benefits-from-a-real-world-switch-from-cvs-to-darcs.html Benefits from a real world switch from CVS to darcs]
+* Implementation details of <code>darcs</code> show motivating examples for [[generalised algebraic datatype]]s. The motivations are described in David Roundy's slides [http://darcs.net/fosdem_talk/talk.pdf 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).
+* See [http://web.archive.org/web/20070409170354/http://darcs.net/DarcsWiki/Talks also other talks] on <code>darcs</code>. One of them ([cufp.galois.com/2005/slides/DavidRoundy.pdf The Myth and Reality of using Haskell in the ‘Real World’]) discusses a more general topic: usefulness of Haskell (in real life) and in general, the power of (lazy) functional programming.
+* [http://wiki.darcs.net/ConfictMiseryAnalysis Conflict bug] -(a problem in Darcs-1)
+* Another free [http://patch-tag.com darcs hosting] (for open source projects) at patch-tag.com
 [[Category:Tools]]