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(ns webdav
  (:require [clojure.string :as str]
            [clojure.data.xml :as xml]
            [org.httpkit.server :as hk-server]))

;; add the XML namespace that we'll use later
(xml/alias-uri 'd "DAV:")

(defn dissoc-in
  "Should be in the standard library..."

littleli

Meld

A minimal example of creating a (mostly) working FUSE filesystem using Clojure. NOTE: I have only tested this with OSX, and it assumes you have already installed libfuse.

Trying it out

Create an empty directory at /tmp/meld to serve as your mount point, put these files in a directory called meld, then:

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(ns radix
  (:require [clojure.string :as string]))
(use 'clojure.java.io)
(use 'clojure.pprint)

(println "Loading names... ")
(time (def names
    (with-open 
      [rdr (reader 
            "/usr/share/dict/ProperNames")]

littleli

Introductory resources

• High level overview https://yogthos.github.io/ClojureDistilled.html
• Interactive exercises http://clojurescriptkoans.com/
• More interactive exercises https://www.4clojure.com/
• Community-powered Clojure courses https://clojurecademy.com/
• Getting started guide https://grison.me/2020/04/04/starting-with-clojure/
• Interactive book https://www.maria.cloud/
• Interactive workbook http://viewer.gorilla-repl.org/view.html?source=github&user=lspector&repo=clojinc&path=worksheet.clj
• Clojure by example https://github.com/inclojure-org/clojure-by-example

littleli

package sandbox;

import java.util.Arrays;
import java.util.Random;

public class SoABenchmark {

	public static Random rand = new Random(9001);
	public static int NUM_LABELS = 10;
	public static Struct[] aos;

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Spike

I looked into the state of GraalVM and Clojure and wrote some small work-related scripts.

GraalVM Build Tools

• Downloaded GraalVM and set $GRAALVM_HOME
• Found two main libraries for building GraalVM CLIs - https://github.com/luchiniatwork/cambada#packaging-as-a-native-image and https://github.com/taylorwood/clj.native-image (or https://github.com/taylorwood/lein-native-image for the lein equivalent). I chose clj.native-image as it seemed more focused on doing one thing well.
• First tried its template example which was easy to follow.
• Then added a graalvm build to one of our small cli tools
• Found it to be pretty straightforward except for a stdout flushing issue that was trivial to fix

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The Pledge

One thing that always made me a little sad about transducers was how map lost its ability to iterate multiple collections in parallel. This is actually my favorite feature of map. For example:

(map + (range 5) (range 5 10))
=> (5 7 9 11 13)

One somewhat practical use of this is if you want to compare two sequences, pairwise, using a comparator. Though I wish that every? took multiple collections, this is an adequate substitute:

littleli

Introductory Material

• Add Graal JIT Compilation to Your JVM Language in 5 Steps, A Tutorial http://stefan-marr.de/2015/11/add-graal-jit-compilation-to-your-jvm-language-in-5-easy-steps-step-1/

• The SimpleLanguage, an example of using Truffle with great JavaDocs https://github.com/graalvm/simplelanguage

• Truffle Tutorial, Christan Wimmer, PLDI 2016, 3h recording https://youtu.be/FJY96_6Y3a4 Slides

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Create Android Studio Command-line Launcher

0. Open Android Studio
1. Go to: Tools > Create Command-line Launcher
2. Leave as default, Press OK

Configure Git to use Android Studio as default Diff Tool

1. Add the following lines to your .gitconfig

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Latency Comparison Numbers
--------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD