stuarthalloway

;; clojure.spec's missing piece, work in progress
;; this is only halfway done, somebody else will need to do the other 95%

(require
 '[clojure.spec :as s]
 '[clojure.spec.test :as test])

(defn naive-english-explain
  "Copy and paste this into your app. Figure out what it does by
trying it in production."

gititGoro

Setting up a private ethereum blockchain for development and pointing your wallet at it

Ethereum tutorials all advise downloading the Mist wallet and beginning dev. The only problem is that the testnet and real blockchain are huge and take hours to download. What follows is a recipe for quickly setting up a small blockchain and pre-mining it with some test ethereum

The following is done in Linux but will work in MacOS and should have equivalent command line options in Windows. Where I don't give detailed instructions, it's because a quick google search will fill in the blanks.

Install geth https://github.com/ethereum/go-ethereum/wiki/geth

install Mist https://github.com/ethereum/mist/releases

borkdude

(ns text-xform
  (:require [clojure.java.io :as io]
            [clojure.string :as str]
            [cheshire.core :as json])
  (:import [java.io BufferedReader]))

;;;; inspired by https://tech.grammarly.com/blog/building-etl-pipelines-with-clojure

(def db (atom 0))

jmlsf

Using JavaScript Libraries from ClojureScript

Using JavaScript libraries from ClojureScript involves two distinct concerns:

1. Packaging the code and delivering it to the browser
2. Making ClojureScript code that accesses JavaScript libraries safe for advanced optimization

Right now, the only single tool that solves these probems reliably, optimally, and with minimal configuration is shadow-cljs, and so that is what I favor. In paricular, shadow-cljs lets you install npm modules using npm or yarn and uses the resulting package.json to bundle external dependencies. Below I describe why, what alternatives there are, and what solutions I disfavor at this time.

Packaging and Delivering Code

mfikes

Usage

Start up the new cljs.main with Node:

clj -Sdeps '{:deps {org.clojurescript {:git/url "https://github.com/clojure/clojurescript" :sha "3f4084efcb5cd92cceb8ca30765144691d8cfd7e"}}}' -m cljs.main -re node

The above works by specifying ClojureScript as a "git dep" and you can ensure that you are running the very latest by replacing the :sha value with the latest commit SHA at https://github.com/clojure/clojurescript.

mfikes

First start up the REPL by issuing this command:

clj -Sdeps '{:deps {github-mfikes/e00202b2de7cc2352fedcf92b1fe60dc {:git/url "https://gist.github.com/mfikes/e00202b2de7cc2352fedcf92b1fe60dc" :sha "68ef581813e08a92bd52e7beeea1535ab7b3337f"}}}' -m cljs.main -i @index.cljs -r

Once the REPL is waiting for the browser to connect, if it doesn't automatically, open http://localhost:9000 in your browser.

You will now be running Bocko. The following forms evaluated in the REPL will draw an American flag.

plexus

(ns defwrapper
  (:require [clojure.string :as str]))

(set! *warn-on-reflection* true)

(defn class-methods [^Class class]
  (seq (.getMethods class)))

(defn constructors [^Class klazz]
  (.getDeclaredConstructors klazz))

olivergeorge

Introduction

Stuart talking about them as part of the Day of Datomic videos:

https://youtu.be/ZP-E2IgqKfA?t=2412

Simple data structure

Simple data structure for anomalies.

dive

;;; package --- Fix permissions for Emacs.app on macOS Catalina
;;; Author: Artem Loenko
;;; Mail-To: <artyom.loenko@mac.com>
;;; Commentary:
;;; Code:

(defconst _default-emacs-app-plist-path "/Applications/Emacs.app/Contents/Info.plist")
(defconst _temp-buffer-name "*fixing Emacs permissions*")
(defconst _temp-buffer (get-buffer-create _temp-buffer-name))
(with-current-buffer _temp-buffer (erase-buffer))

ericnormand

delete from a vector

Clojure's vectors let you efficiently get a value given an integer index. Often, I want to remove a value from a vector at a certain index. This doesn't exist in the core library, so I wind up writing it each time. The question is how to do it in an efficient way?

Here's the task: write a function delete-at that takes a vector and an index and returns a new vector with the item at the index removed. The new vector should be one shorter than the argument.

(defn delete-at [v i]
  ;; your code here
 )