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@alandipert
alandipert / kahn.clj
Last active June 24, 2023 17:59
Kahn's topological sort in Clojure
;; Copyright (c) Alan Dipert. All rights reserved.
;; The use and distribution terms for this software are covered by the
;; Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
;; 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.
(ns alandipert.kahn
(:require [clojure.set :refer [difference union intersection]]))
@alandipert
alandipert / reinvoke.cljs
Last active June 22, 2019 00:20
It's sweet that IFn is a protocol in ClojureScript
(extend-type js/RegExp
cljs.core/IFn
(-invoke ([this s] (re-matches this s))))
(#"foo.*" "foobar") ;=> "foobar"
(#"zoo.*" "foobar") ;=> nil
(filter #".*foo.*" ["foobar" "goobar" "foobaz"]) ;=> ("foobar" "foobaz")
@bobby
bobby / datomic-helpers.clj
Created July 20, 2012 14:12
Some Datomic helpers I sometimes use with ring or pedestal-service apps
(ns datomic-helpers
(:require [datomic.api :as d]))
;;; Expose Datomic vars here, for convenience
;;; Ring middleware
(defn wrap-datomic
"A Ring middleware that provides a request-consistent database connection and
value for the life of a request."
@ptaoussanis
ptaoussanis / free-port.clj
Created December 14, 2012 06:28
A little utility to allow simple redeployment of Clojure web servers with zero downtime, and without the need for a proxy or load balancer. Just wrap any port-binding calls, and the utility will auto kill pre-existing servers as necessary. *nix only. Based on the blog post by Feng Shen, http://shenfeng.me/fast-restart-clojure-webapp.html
;; (require '[clojure.string :as str] '[clojure.java.shell :as shell] '[taoensso.timbre :as timbre])
(defn with-free-port!
"Attempts to kill any current port-binding process, then repeatedly executes
nullary `bind-port!-fn` (which must return logical true on successful
binding). Returns the function's result when successful, else throws an
exception. *nix only.
This idea courtesy of Feng Shen, Ref. http://goo.gl/kEolu."
[port bind-port!-fn & {:keys [max-attempts sleep-ms]

Falsehoods programmers believe about prices

  1. You can store a price in a floating point variable.
  2. All currencies are subdivided in 1/100th units (like US dollar/cents, euro/eurocents etc.).
  3. All currencies are subdivided in decimal units (like dinar/fils)
  4. All currencies currently in circulation are subdivided in decimal units. (to exclude shillings, pennies) (counter-example: MGA)
  5. All currencies are subdivided. (counter-examples: KRW, COP, JPY... Or subdivisions can be deprecated.)
  6. Prices can't have more precision than the smaller sub-unit of the currency. (e.g. gas prices)
  7. For any currency you can have a price of 1. (ZWL)
  8. Every country has its own currency. (EUR is the best example, but also Franc CFA, etc.)
@XVilka
XVilka / TrueColour.md
Last active May 28, 2024 17:42
True Colour (16 million colours) support in various terminal applications and terminals

THIS GIST WAS MOVED TO TERMSTANDARD/COLORS REPOSITORY.

PLEASE ASK YOUR QUESTIONS OR ADD ANY SUGGESTIONS AS A REPOSITORY ISSUES OR PULL REQUESTS INSTEAD!

@swannodette
swannodette / om_data.cljs
Last active January 9, 2021 16:09
Om + DataScript
(ns om-data.core
(:require [om.core :as om :include-macros true]
[om.dom :as dom :include-macros true]
[datascript :as d]))
(enable-console-print!)
(def schema {})
(def conn (d/create-conn schema))
@allgress
allgress / reagent_datascript.cljs
Last active February 16, 2023 21:16
Test use of DataScript for state management of Reagent views.
(ns reagent-test.core
(:require [reagent.core :as reagent :refer [atom]]
[datascript :as d]
[cljs-uuid-utils :as uuid]))
(enable-console-print!)
(defn bind
([conn q]
(bind conn q (atom nil)))
@xavriley
xavriley / README.md
Last active December 30, 2023 12:17
Original NES Mario Theme for Sonic Pi

Making Chiptune Music using Sonic Pi v2.0

Warning: this might not work on a RaspberryPi yet

I was curious about making retro gaming sounds using Sonic Pi. A couple of months and a lot of Googling later, here's the original Mario Bros theme as it was heard on the NES console.

I'm (just about) old enough to remember rushing home from school to play this game at Philip Boucher's house, sitting cross-legged in front of the TV till my feet got pins and needles. Working out how to recreate it for Sonic Pi was a lot of fun!

Getting the sounds of the NES chip

@bsima
bsima / boot-project.clj
Last active August 29, 2015 14:10
Sometimes you want to use boot as a scripting platform on top of Leinengen. Paste this code at the top of your build.boot file. It reads in the project.clj file and stores it as a map named "project" which you can then use with `set-env!` to setup your environment.
(set-env! :dependencies '[[leiningen-core "2.5.0"]])
(use 'leiningen.core.project)
(eval (read-string (slurp "project.clj")))
(set-env!
:source-paths (:source-paths project)
:resource-paths (:resource-paths project)
:dependencies (:dependencies project))