Using Psc-Package from your project

Frequently used commands

# install or update the dependencies listed in psc-package.json
$ psc-package install

# install or update the package and add it to psc-package.json if not listed
$ psc-package install <package>

# list available commands
$ psc-package --help

Create a project

A new package can be created using psc-package init. This will:

  • Create a simple psc-package.json file based on the current compiler version
  • Add the Prelude as a dependency (this can be removed later)
  • Sync the local package database (under the .psc-package/ directory) by cloning any necessary repositories.

Add dependencies

To add a dependency, either:

  • Use the install <package name> command, which will update the project configuration automatically, or
  • Modify the psc-package.json file, and sync manually by running the install command (previously update).

Build a project

Active project dependencies and project source files under src can be compiled using the build command.

This command is provided as a convenience until external tools add support for psc-package. It might be removed in future.

Query the local package database

The local package database can be queried using the following commands:

  • sources - list source directories for active package versions. This can be useful when building a command for, say, running PSCi.
  • dependencies - list all transitive dependencies

Local package sets

In psc-package.json, you can set "source" to be a path to a local file:

  "name": "name",
  "set": "local",
  "source": "packages.json",
  "depends": [

From here, you can generate a local packages.json file in any way you please and use this package set directly. Consider if you use Dhall:

let upstream = sha256:0a6051982fb4eedb72fbe5ca4282259719b7b9b525a4dda60367f98079132f30

in    upstream
    ⫽ { calpis =
          { dependencies = [ "prelude" ]
          , repo = ""
          , version = "v0.1.0"

This definition takes an existing release and adds the “calpis” package. Then we can generate a package set from this by running Dhall-JSON:

dhall-to-json –file packages.dhall –output packages.json

Then we can install this package expected:

$ psc-package install calpis
Installing calpis
psc-package.json file was updated

$ cat psc-package.json
  "name": "name",
  "set": "local",
  "source": "packages.json",
  "depends": [