The whole tutorial is a cabal project and can be built locally as follows:
$ git clone https://github.com/haskell-servant/servant.git $ cd servant # build $ cabal new-build tutorial # load in ghci to play with it $ cabal new-repl tutorial
The servant stack template includes the working tutorial. To initialize this template, run:
$ stack new myproj servant $ cd myproj # build $ stack build # start server $ stack exec myproj-exe
The code can be found in the *.lhs files under doc/tutorial/ in the repository. Feel free to edit it while you’re reading this documentation and see the effect of your changes.
Nix users should feel free to take a look at the nix/shell.nix file in the repository and use it to provision a suitable environment to build and run the examples.
Note for Ubuntu users¶
Ubuntu’s packages for ghc, cabal, and stack are years out of date. If the instructions above fail for you, try replacing the Ubuntu packages with up-to-date versions. First remove the installed versions:
# remove the obsolete versions $ sudo apt remove ghc haskell-stack cabal-install
Then install fresh versions of the Haskell toolchain using the ghcup installer.
As of February 2022, one easy way to do this is by running a bootstrap script:
$ curl --proto '=https' --tlsv1.2 -sSf https://get-ghcup.haskell.org | sh
The script is interactive and will prompt you for details about what you want installed and where. To install manually, see the detailed instructions.