This article describes the entire process of writing, packaging and releasing a new Haskell library. If you love programming Haskell, and want to keep doing so, you’ll write some libraries and release them. The lambda revolution isn’t going to happen without your code!
Creating Data.DList, it took about 60 minutes. People often need O(1) append, so about time we had a library for it. Here’s the entire transcript of creating a new Haskell project and releasing it to a public server. I then created a web page for the project, and announced it on the haskell@ mailing list. I used the following tools:
Ready? Here we go!
Script started on Mon Dec 11 13:47:40 2006 $ cd dons/src $ mkdir dlist $ cd dlist $ mkcabal Project name: dlist What license ["GPL","LGPL","BSD3","BSD4","PublicDomain","AllRightsReserved"] ["BSD3"]: What kind of project [Executable,Library] [Executable]: Library Is this your name? - "Don Stewart " [Y/n]: Is this your email address? - "<dons@cse.unsw.edu.au>" [Y/n]: Created Setup.lhs and dlist.cabal $ cp ~/dons/src/yi/Yi/Lexers.hs . $ ls Lexers.hs Setup.lhs dlist.cabal $ mkdir Data $ mv Lexers.hs Data/DList.hs $ vim Data/DList.hs $ vim dlist.cabal $ darcs init $ darcs add dlist.cabal Setup.lhs Data/ Data/DList.hs $ darcs record --all Shall I record this change? (1/?) [ynWsfqadjkc], or ? for help: a What is the patch name? Initial import of dlist package Do you want to add a long comment? [yn]n Finished recording patch 'Initial import of dlist package' $ runhaskell Setup.lhs configure --prefix=/home/dons Setup: Warning: No exposed modules or executables in this package. Setup: Error: Non-empty library, but empty exposed modules list. Cabal may not build this library correctly $ vim dlist.cabal $ runhaskell Setup.lhs configure --prefix=/home/dons Configuring dlist-0.1... configure: /home/dons/bin/ghc-pkg configure: Dependency base-any: using base-2.0 configure: Using install prefix: /home/dons configure: Binaries installed in: /home/dons/bin configure: Libraries installed in: /home/dons/lib/dlist-0.1/ghc-6.6 configure: Private binaries installed in: /home/dons/libexec configure: Data files installed in: /home/dons/share/dlist-0.1 configure: Using compiler: /home/dons/bin/ghc configure: Compiler flavor: GHC configure: Compiler version: 6.6 configure: Using package tool: /home/dons/bin/ghc-pkg configure: Using ar found on system at: /usr/bin/ar configure: Using haddock found on system at: /home/dons/bin/haddock configure: No pfesetup found configure: Using ranlib found on system at: /usr/bin/ranlib configure: Using runghc found on system at: /home/dons/bin/runghc configure: Using runhugs found on system at: /home/dons/bin/runhugs configure: Using happy: /home/dons/bin/happy configure: Using alex: /home/dons/bin/alex configure: Using hsc2hs: /home/dons/bin/hsc2hs configure: No c2hs found configure: Using cpphs: /home/dons/bin/cpphs configure: No greencard found Preprocessing library dlist-0.1... Building dlist-0.1... $ runhaskell Setup.lhs build Preprocessing library dlist-0.1... Building dlist-0.1... Data/DList.hs:17:2: parse error on input `DList' $ vim Data/DList.hs +17 $ runhaskell Setup.lhs build Preprocessing library dlist-0.1... Building dlist-0.1... [1 of 1] Compiling Data.DList ( Data/DList.hs, /usr/obj/cabal/Data/DList.o ) /usr/bin/ar: creating /usr/obj/cabal/libHSdlist-0.1.a $ runhaskell Setup.lhs install Installing: /home/dons/lib/dlist-0.1/ghc-6.6 & /home/dons/bin dlist-0.1... Registering dlist-0.1... Reading package info from ".installed-pkg-config" ... done. Saving old package config file... done. Writing new package config file... done. $ darcs amend-record Mon Dec 11 14:20:56 EST 2006 Don Stewart <dons@cse.unsw.edu.au> * Initial import of dlist package Shall I amend this patch? [yNvpq], or ? for help: y hunk ./Data/DList.hs 15 -module Data.DList +module Data.DList ( Shall I add this change? (1/?) [ynWsfqadjkc], or ? for help: y hunk ./dlist.cabal 10 +Exposed-modules: Data.DList Shall I add this change? (2/?) [ynWsfqadjkc], or ? for help: y Finished amending patch: Mon Dec 11 14:21:53 EST 2006 Don Stewart <dons@cse.unsw.edu.au> * Initial import of dlist package $ runhaskell Setup.lhs haddock Preprocessing library dlist-0.1... Running Haddock for dlist-0.1... Warning: cannot use package base-2.0: HTML directory /home/dons/share/ghc-6.6/html/libraries/base does not exist. /usr/obj/cabal/tmp/Data/DList.hs:"/usr/obj/cabal/tmp/Data/DList.hs": 37:1: parse error in doc string: [TokPara] $ vim Data/DList.hs +37 $ runhaskell Setup.lhs haddock Preprocessing library dlist-0.1... Running Haddock for dlist-0.1... Warning: cannot use package base-2.0: HTML directory /home/dons/share/ghc-6.6/html/libraries/base does not exist. $ w3m -dump dist/doc/html/index.html dlist-0.1: Contents Index dlist-0.1: Differences lists: lists supporting efficient append Modules show/hideData Data.DList Produced by Haddock version 0.8 $ mkdir tests $ vim tests/Properties.hs $ vim tests/Parallel.hs $ cd tests $ runhaskell Properties.hs 2: singleton : OK, 1000 tests. 1: model : OK, 1000 tests. 2: snoc : OK, 1000 tests. 1: append : OK, 1000 tests. $ cd .. $ darcs add tests $ darcs add tests/Parallel.hs tests/Properties.hs $ darcs whatsnew -s M ./Data/DList.hs -1 +1 A ./tests/ A ./tests/Parallel.hs A ./tests/Properties.hs $ darcs record --all ... Shall I record this change? (6/?) [ynWsfqadjkc], or ? for help: y What is the patch name? Add QuickChecks Finished recording patch 'Add QuickChecks' $ darcs setpref test "cd tests ; runhaskell Properties.hs" Changing value of test from '' to 'cd tests ; runhaskell Properties.hs' changepref test cd tests ; runhaskell Properties.hs Shall I record this change? (1/?) [ynWsfqadjkc], or ? for help: y What is the patch name? pre run tests on each commit Do you want to add a long comment? [yn]n Running test... 2: singleton : OK, 1000 tests. 2: snoc : OK, 1000 tests. 1: model : OK, 1000 tests. 2: append : OK, 1000 tests. Test ran successfully. Looks like a good patch. Finished recording patch 'run tests on each commit' $ darcs whatsnew -s No changes! $ darcs tag What is the version name? 0.1 dlist 0.1 Finished tagging patch 'TAG dlist 0.1' $ runhaskell Setup.lhs sdist Building source dist for dlist-0.1... *** Exception: LICENSE: copyFile: does not exist (No such file or directory) $ cp ~/pqc/LICENSE . $ vim LICENSE $ darcs add LICENSE $ darcs record addfile ./LICENSE Shall I record this change? (1/?) [ynWsfqadjkc], or ? for help: y ... Shall I record this change? (2/?) [ynWsfqadjkc], or ? for help: y What is the patch name? add license Do you want to add a long comment? [yn]n Running test... 2: singleton : OK, 1000 tests. 2: snoc : OK, 1000 tests. 1: model : OK, 1000 tests. 2: append : OK, 1000 tests. Test ran successfully. Looks like a good patch. Finished recording patch 'add license' $ vim README $ darcs add README $ darcs record --all What is the patch name? Add a readme Do you want to add a long comment? [yn]n Running test... 2: singleton : OK, 1000 tests. 2: snoc : OK, 1000 tests. 1: model : OK, 1000 tests. 2: append : OK, 1000 tests. Test ran successfully. Looks like a good patch. Finished recording patch 'Add a readme' $ ls Data LICENSE README Setup.lhs _darcs dist dlist.cabal tests $ darcs dist -d dlist-0.1. Created dist as dlist-0.1.tar.gz $ darcs whatsnew -s No changes! $ darcs put pill00.cse.unsw.edu.au:/home/chakcvs/darcs/dlist/ Finished applying... Script done on Mon Dec 11 15:04:54 2006
Control.Monad.Writer 