Gert Goet eval

An opinionated list of excellent Clojure learning materials

These resources (articles, books, and videos) are useful when you're starting to learn the language, or when you're learning a specific part of the language. This an opinionated list, no doubt. I've compiled this list from writing and teaching Clojure over the last 10 years.

🔴 Mandatory (for both beginners and intermediates)
🟩 For beginners
🟨 For intermediates

HOWTO install `#user/uri` reader extension in Clojure/Script

We use #user/uri rather than unquaified #uri per Alex Miller comment in the Ask Clojure thread.

License: public domain

A backup copy of the code from https://david.rothlis.net/declarative-schema-migration-for-sqlite/

(I'm enjoying doing these raw, barely edited writeups; I hope they're useful to you too)

Feature flags

This is my own writeup on feature flags; for a deep dive I'd recommend something like Martin Fowler's article (https://martinfowler.com/articles/feature-toggles.html).

So. Feature flags. The basic idea that you'll store configuration/values on a database/service somewhere, and by changing those values, you can change the user experience/features for a user on the fly.

Let's say that you're building a new feature, called 'new-button' which changes the color of buttons, which is currently red, to blue. Then you'd change code that looks like this -

	(require '["vscode" :as vscode]
	'[clojure.string :as str])

	(defn insert-num
	[]
	(let [editor vscode/window.activeTextEditor
	position (.-active (.-selection editor))
	doc (.-document editor)
	line (-> (.lineAt doc position) (.-text))
	character (last (str/trim line))

	Here's a quick dockerfile:

	----------------8<-------------[ cut here ]------------------
	FROM debian:latest

	RUN apt-get update && apt-get install -y nodejs npm
	----------------8<-------------[ cut here ]------------------

	save that as Dockerfile and do: docker build -t node-builder .

	(ns utils.re-frame
	(:require [cljs.compiler :as cljsc]))

	(defn- anonymous-function-declaration? [form]
	(and (list? form)
	(= 'fn (first form))
	(vector? (second form))))

	(defn- query-id->js-fn-name [query-id]
	(let [ns-part (when-let [ns-part (namespace query-id)]

	#!/usr/bin/env bb

	(ns dev
	(:import java.lang.ProcessBuilder$Redirect)
	(:require [clojure.java.io :as io]))

	(defn cljs []
	(let [cmd ["clojure" "-A:cljs/dev"]
	pb (doto (ProcessBuilder. cmd)
	(.redirectOutput ProcessBuilder$Redirect/INHERIT)

	<html>
	<head>
	<link href="https://cdnjs.cloudflare.com/ajax/libs/prism/1.17.1/themes/prism-tomorrow.min.css" rel="stylesheet" />
	</head>
	<body>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.17.1/components/prism-core.min.js"></script>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.17.1/plugins/autoloader/prism-autoloader.min.js"></script>
	<pre>
	<code class="language-clojure">
	(defn foo []

	#!/usr/bin/env bash

	set -oe pipefail

	jarPath=$1

	# inspired by metabase
	# Disable limit to amount of time spent in GC. Better slow than not working at all
	JAVA_OPTS="$JAVA_OPTS -XX:-UseGCOverheadLimit"
	JAVA_OPTS="$JAVA_OPTS -XX:+UseConcMarkSweepGC"

Gert Goet eval

An opinionated list of excellent Clojure learning materials

Table of contents

HOWTO install #user/uri reader extension in Clojure/Script

Feature flags

HOWTO install `#user/uri` reader extension in Clojure/Script