Clojure with Leiningen Development Environment

Everything is an expression!

Every coherent block of code you write will return a value.

• Statement: An action to be performed
  • does not return a value
    • like writing an if statement
• Expression: A syntactic unit that can be evaluated
  • returns a value
    • like calling a function

Syntax!

Code is data

Requirements

• CLI/Terminal
  • Install lein as an executable from $PATH
  • Run lein
  • lein --version
• VScode
  • Install calva REPL extension

Installation

• Run lein repl in VSCode Terminal
  • nREPL server started on port 62833 on host 127.0.0.1 - nrepl://127.0.0.1:62833
  • Copy 62833
• Hit "REPL" at bottom tab nav VSCode (this is the calva ext)
  • Select "Connect to a running REPL, not in your project"
  • Select "Leiningen"
  • Input localhost:62833
• Window on right prints out output of all expressions

Usage

• Select Clojure code expressions in left editor and (CTRL ENTER):

  • > Calva: Evaluate Current Form (or selection, if any

    clj꞉user꞉> 
    Hello World!
    nil

  • Whatever value of the expressions selected is printed on the right window as well as the return value of the last expression (println is a side effect)

• You can also use the VSCode terminal for one-off commands

App

• cd ..
• lein new app --to-dir lein-clojure-lib --force

License

Copyright © 2023 Joem Elias Sanez

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.