Defining aliases to do more with Clojure tools

Aliases are used with Clojure tools to provide additional configuration and are only used when explicitly added to the clojure command.

Aliases can be used to add:

  • extra dependencies and paths
  • community tools (rebel readline, clj-new, etc.)

Aliases can be defined in a project deps.edn or be available to all projects via the ~/.clojure/deps.edn configuration file.

Hint::practicalli/clojure-deps-edn adds common aliases and tools

Create a fork of the practicalli/clojure-deps-edn on GitHub. Clone that fork to instantly have access to dozens of tools for Clojure software development.

All tools are provided via libraries and are only downloaded on first use or if versions of libraries are updated.

Using an alias

An alias is used via the -A option to the clojure command:

  1. clojure -A:my-task

Multiple aliases can be used together

  1. clojure -A:test:test-runner

Hint::Only one main namespace

If multiple aliases set a main namespace, the first alias to do so will be used to start the -main function. If that first alias never terminates or terminates the clojure command, then further -main functions from set main namespaces will not be run.

An alias for a community tool

Use the rebel community tool by including its alias.

  1. clojure -A:rebel

This alias adds the library dependency for the rebel readline project and defines the main namespace. The namespace is where the -main function is located that will start rebel readline.

  1. {:aliases
  2.    :rebel
  3.      {:extra-deps {com.bhauman/rebel-readline {:mvn/version "0.1.4"}}
  4.       :main-opts  ["-m" "rebel-readline.main"]}
  5. } ;; End of aliases

Including paths, deps and main-opts

The Cognitect Lab test runner included the test directory in the class path, so test code will be included when run with this alias.

The test runner dependency is pulled from a specific commit shared on GitHub (defined as a Git SHA).

The main namespace is set to that library and the -main function is called when using this alias.

  1. {:aliases
  2.     :test-runner-cognitect
  3.     {:extra-paths ["test"]
  4.      :extra-deps  {com.cognitect/test-runner
  5.                   {:git/url "https://github.com/cognitect-labs/test-runner.git"
  6.                    :sha     "f7ef16dc3b8332b0d77bc0274578ad5270fbfedd"}}
  7.      :main-opts   ["-m" "cognitect.test-runner"]}
  10. }

You can use and legal Clojure keyword name for an alias and include multiple aliases with the clojure command. For example in this command we are combining three aliases: clojure -A:my-task:my-build:my-prefs