par

A Clojure(Script) library designed to print-and-return values.

Intended to wrap existing forms in your source code so they can be observed without changing the execution of the program.

The screen recording above shows the editor (left), and Chrome DevTools Console (right).

The sequence of edits demonstrates each of the 3 arities for par.core/?.

Usage

Add as a dependency to your project:

[org.clojars.paintparty/par "1.0.0"]

Import into your namespace:

(ns myns.core
  (:require
    [par.core :refer [? !? ?+ !?+]]))

;; :refer-macros syntax will work as well.
(ns myns.core
  (:require
    [par.core :refer-macros [? !? ?+ !?+]]))

?

Use the par.core/? macro to print the form and resulting value. You should expect the same console output whether you are using Clojure or ClojureScript:

(? (+ 1 2))

The example above would print the following:

(+ 1 2) => 3

If you would like to add some commentary to your logs:

(? "Note to self" (+ 1 2))

The above will prepend the first argument to the output.
The output will be italicized, with a leading "; ".
The form that is being evaluated will not be printed.
The example above would print the following:

; Note to self
 => 3

If you would like both the commentary and form to be printed:

(?+ "Note to self" :form (+ 1 2))

The example above would print the following:

; Note to self
(+ 1 2) => 3

?+

When you want to log from inside a defmacro, or inside a function that is being called by a defmacro, the ?+ macro should be used. It has the exact same signature as ?.

!? and !?+

par.core/!? and par.core/!?+ are both no-op macros, useful when you want to temporarily silence the printing on a form that is already wrapped by ? or ?+.

License

Copyright © 2020-2021 Jeremiah Coyle

This program and the accompanying materials are made available under the terms of the Eclipse Public License 2.0 which is available at http://www.eclipse.org/legal/epl-2.0.

This Source Code may also be made available under the following Secondary Licenses when the conditions for such availability set forth in the Eclipse Public License, v. 2.0 are satisfied: GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version, with the GNU Classpath Exception which is available at https://www.gnu.org/software/classpath/license.html.