From b6b2ca5d19806a9ef13587b4988aa53ae7812878 Mon Sep 17 00:00:00 2001 From: Arun Isaac Date: Wed, 8 Mar 2017 23:28:34 +0530 Subject: [PATCH] gnu: Add python2-larch. * gnu/packages/python.scm (python2-larch): New variable. Signed-off-by: Marius Bakke --- gnu/packages/python.scm | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/gnu/packages/python.scm b/gnu/packages/python.scm index 2e68db72d7..ee785c26ed 100644 --- a/gnu/packages/python.scm +++ b/gnu/packages/python.scm @@ -13567,3 +13567,34 @@ (define-public python2-tracing matters when code is run in production mode. The actual logging still happens using the @code{logging} library.") (license license:gpl3+))) + +(define-public python2-larch + (package + (name "python2-larch") + (version "1.20151025") + (source + (origin + (method url-fetch) + (uri (string-append + "http://git.liw.fi/cgi-bin/cgit/cgit.cgi/larch/snapshot/larch-" + version ".tar.gz")) + (sha256 + (base32 + "1p4knkkavlqymgciz2wbcnfrdgdbafhg14maplnk4vbw0q8xs663")))) + (build-system python-build-system) + (arguments + `(#:python ,python-2)) + (propagated-inputs + `(("python2-tracing" ,python2-tracing))) + (home-page "https://liw.fi/larch/") + (synopsis "Python copy-on-write B-tree library") + (description "@code{python2-larch} is an implementation of +particular kind of B-tree, based on research by Ohad Rodeh. See +@url{http://liw.fi/larch/ohad-btrees-shadowing-clones.pdf} for details +on the data structure. + +The distinctive feature of this B-tree is that a node is never +(conceptually) modified. Instead, all updates are done by +copy-on-write. This makes it easy to clone a tree, and modify only the +clone, while other processes access the original tree.") + (license license:gpl3+)))