john2x

Clojure Destructuring Tutorial and Cheat Sheet

(Related blog post)

Simply put, destructuring in Clojure is a way extract values from a datastructure and bind them to symbols, without having to explicitly traverse the datstructure. It allows for elegant and concise Clojure code.

Vectors and Sequences

candera

A little Clojure configuration reader

This is a handy bit of code I've written more than once. I thought I'd throw it in here so I can refer back to it later. Basically, it lets you read a config file to produce a Clojure map. The config files themselves can contain one or more forms, each of which can be either a map or a list. Maps are simply merged. Lists correspond to invocations of extension points, which in turn produces a map, which is merged along with everything else.

An Example

Consider the following files:

names.edn

michiakig

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; Ant sim ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;   Copyright (c) Rich Hickey. All rights reserved.
;   The use and distribution terms for this software are covered by the
;   Common Public License 1.0 (http://opensource.org/licenses/cpl.php)
;   which can be found in the file CPL.TXT at the root of this distribution.
;   By using this software in any fashion, you are agreeing to be bound by
;   the terms of this license.
;   You must not remove this notice, or any other, from this software.

;dimensions of square world

ghoseb

;;
;; NS CHEATSHEET
;;
;; * :require makes functions available with a namespace prefix
;;  and optionally can refer functions to the current ns.
;;
;; * :import refers Java classes to the current namespace.
;;
;; * :refer-clojure affects availability of built-in (clojure.core)
;;   functions.