~bzr-pqm/bzr/bzr.dev

6 by mbp at sourcefrog
import all docs from arch
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Darcs compared to Arch
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======================
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Simpler to use; perhaps harder to completely understand.
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Always local; always fast.
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Patch commution is slow and perhaps doesn't clearly do what people
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want.  
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Too slow!
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Can't reliably get back to any previous point.  Explicitly not
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addressing source archive/librarian function.
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Loads everything into memory.
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Written in Haskell.
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A really simple pre-commit check hook is remarkably useful.
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http://www.scannedinavian.org/DarcsWiki/DifferencesFromArch
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47 by mbp at sourcefrog
notes on more good bits from darcs: partial commit, etc
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Sometimes useful to be able to set email per-branch, for people who
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work on different projects under different personas.
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6 by mbp at sourcefrog
import all docs from arch
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Token replace
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-------------
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Very cute; possibly handy; not absolutely necessary in most places.
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Somewhat limited by the requirement that it be reversible.
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This is one of very few cases where it does seem necessary that we
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store deltas, rather than tree states.  But that seems to cause other
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problems in terms of being able to reliably sign revisions.
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This can perhaps be inferred by a smart 3-way merge tool.  Certainly
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you could have it do sub-line merges.
47 by mbp at sourcefrog
notes on more good bits from darcs: partial commit, etc
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Partial commit
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--------------
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darcs allows you to commit only some of the changes to a single file.
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This is like the common feature of commiting only a subset of changed
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files, but taken to a higher level.
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It is useful more often than one might think: it is common to fix some
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documentation 'on the wing' and while strictly it should be in a
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separate commit it is not always worth the hassle to back out changes,
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fix the docs, then do the real change.  Similarly for making a
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separate branch.
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Although the idea is very good, the current darcs implementation is
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limited to selecting by patch hunk, which means that neighbouring
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changes cannot be separated.  Fixing this probably means having some
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kind of pluggable GUI to build the file-to-be-committed or an edited
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patch, possibly using something like meld, emacs, or dirdiff.  Another
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approach some people might like is editing the diff file to chop out
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hunks.
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I don't think this needs to be on by default, as it is in darcs.  It
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is usual to commit all the changes.
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For this to work safely, it is good to have a commit hook that
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builds/tests the tree.  Of course this needs to be evaluated against
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the tree as it will be committed (taking account of partial commits),
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not the working tree.
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75 by mbp at sourcefrog
more notes on darcs
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Schwern
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-------
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* http://www.scannedinavian.org/DarcsWiki/SchwernLikesDarcs
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* http://www.scannedinavian.org/DarcsWiki/SchwernHatesDarcs
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I think we hit most of these; more evidence for the hypothesis that
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what people really like about darcs is the simple interface not the
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patch-commutation model.