WREPL - Configure the REPL with Integrant

Run a REPL where all "letters" allow for dependency injection. This allows easier mixing and matching components you want to have in your REPL. E.g. use rebel-readline, but use your own pretty-printer; or write your own specialized prompts like "REST-REPL", to talk to the web (see examples).

Note: Since version 0.2 this integrates now with the Clojure CLI tools; if you are interested in the stand-alone version, use the 0.1.X branch.

Examples

Check the example folder.

• deps.edn : Clojure CLI configuration with two aliases. You can put the aliases in your ~/.config/clojure/deps.edn file.
• wrepl : Run a WREPL with rebel-readline and puget pretty-printing with the colors configured
• wrepl.edn : Configuration for the above; you can put this file at ~/.wrepl/wrepl.edn.
• rest-repl : Same like above, but runs REST-REPL; note the -b rest-repl arguments, to give the configuration a different base-name, so different things may be configured.
• rest-repl.edn : Configuration for the above; you can put this file at ~/.wrepl/rest-repl.edn

Options

The main from WREPL has the following options:

 -b, --base-name base-name  Base name for the user config to search for; e.g. $HOME/.wrepl/$BASENAME.edn (default: wrepl)
 -c, --config config.edn    Read the integrant system config from this file and merge it with the default
     --no-user-config       Don't load the default user config
 -i, --init script.clj      Run the given file before the first prompt
 -e, --eval string          Evaluate the expression (after --init if both given)
 -h, --help

Configuration

Configuration is done with an EDN file, that immutant will read. So a basic understanding of that syntax is helpful.

By default, WREPL will attempt to find and load the files or resources in the following order:

• File: ".$BASENAME.edn"
• File: ".wrepl/$BASENAME.edn"
• File: "$HOME/.$BASENAME.edn"
• File: "$HOME/.wrepl/$BASENAME.edn"
• Resource: "$BASENAME.edn"

Where $BASENAME is the configured base name given as an argument, or the default, wrepl.

Entry points

The main configuration points to override the behaviour. These are basically what REPL to start and what to pass to it, following the example of the clojure.main/repl:

• :wrepl/repl: REPL-Function; this must behave like clojure.main/repl, which is the default
• :wrepl/init: List of functions to run first in started REPL; the default is changing into the user namespace and providing another hook to add more init functions without overwriting the default (named :wrepl/append-init)
• :wrepl/prompt: Function to print a prompt for input; defaults to whatever the REPL provides
• :wrepl/read: Function to read the input; defaults to whatever the REPL provides
• :wrepl/eval: Function to evaluate the read form; defaults to :wrepl.eval/interruptible, which allows to CTRL-C the current running eval.
• :wrepl/print: Function to print the result of the evaluation; defaults to whatever the REPL provides

Default expansion points

There are already some "plugins" the wrepl comes pre-packaged:

• :wrepl.init/in-ns {:ns user}: Change the default namespace of the REPL; run by default
• :wrepl.init/load-file {:filename "$HOME/.wrepl/tools.clj"}: Read and run the given :filename; does restricted variable replacements (see below)
• :wrepl.init/eval {:expr "(+ 1 2 3)"}: Reads the string :expr, evaluates it, and prints the result
• :wrepl.eval/interruptible: eval, that allows CTRL-C of the current running evaluation (used as default)

Replacements

If supported by the configuration (mentioned above) the following replacements are available inside strings:

• $HOME: What Java considers the user home (the property user.home)

Known plugins

• clj-wrepl-puget Color pretty print
• clj-wrepl-rebel-readline Rebel Readline
• clj-wrepl-relative-clj-http Exploring web APIs interactively