CPM: The Curry Package Manager

The Curry Package Manager (CPM) is a tool to distribute and install Curry libraries and applications and manage version dependencies between them. These libraries are organized in packages. There is a central index of all these packages which can easily be downloaded by CPM. The individual packages are currently not stored in a central server but their source can be anywhere. CPM organizes the automatic access to appropriate versions of these packages so that a user does not need to know about these details.

CPM also supports semantic versioning, i.e., it is able to check whether a new minor version of a package is consistent (w.r.t. its API and behavior) with a previous version of the same package.

There are more than 100 packages available (including more than 600 modules). There is a table of all packages with more detailed information (e.g., API documentation). These packages can immediately be downloaded or installed when CPM is installed (see below).

CPM is already part of recent distributions of the Curry systems PAKCS (Version 1.15.0 or higher) and KiCS2 (Version 0.6.0 or higher). If you have some older version of PAKCS or KiCS2, you can also install CPM from its public repository. The installation requires that one of the Curry systems PAKCS or KiCS2 is installed and the executables curry and git are in your path (if curry is not in your path, you can also specify the root location of your Curry system by modifying the definition of CURRYROOT in the Makefile before executing make in step 3). Then perform the following steps to install CPM:

  1> git clone https://git.ps.informatik.uni-kiel.de/curry-packages/cpm.git
  2> cd cpm
  3> make

If this was successful, the binary cypm has been generated in the directory ~/.cpm/bin. This is also the directory where CPM installs binaries of applications distributed as packages. For convenient use, you should add the directory ~/.cpm/bin to your path. Alternatively, you can also put the binary ~/.cpm/bin/cypm somewhere in your path or create a symbolic link from some path directory to this binary.

Now you can clone a copy of the central package index repository by

  > cypm update

Afterwards, you can show a short list of all packages in this index by

  > cypm list

The command

  > cypm info PACKAGE

can be used to show more information about a package.

In order to use a package in your Curry program which you intend to develop, you have to start a new project. Note that your project can also contribute to the Curry packages. Therefore, to initialize it and use other packages, you need a package description file in some project directory. All this can be created by the command cypm new:

  > cypm new myproject

This command creates a new project directory myproject containing an initial package description file package.json and a subdirectory src (together with other template files). Change into the new project directory:

  > cd myproject

If you need some other packages for your project, add them as a dependency in package.json. Then run

  > cypm install

to install all dependencies of the current package. Afterwards, start your interactive Curry environment by

  > cypm curry

and you will be able to load the modules of the current package as well as all dependent packages. In particular, the source directory src is added to your path so that you can directly load any program you have stored in this directory. For instance, if the module Main.curry is stored in the directory src, you can load it into your Curry system (e.g., KiCS2 or PAKCS) by

  > cypm curry :load Main

For further information, look into the manual of CPM.

A detailed description about CPM and its implementation can be found in the following thesis:

A Package Manager for Curry (Jonas Oberschweiber, CAU Kiel, September 2016)

Currently, there is no support for automatically uploading and publishing new packages. However, if you have developed some package that might be of interest to other Curry users, please send the package as a tar or zip file to

  packages (AT) curry-language.org

in order to make it publicly available.