Ben Vandgrift bvandgrift

author of Clojure Applied: from Practice to Practitioner "slightly dirty cop with a heart of gold." #clj, #py, #wordsmithery

bvandgrift / can_pet.js

Last active February 23, 2022 16:43

simple decision logic demo for a friend's son currently javascripting

	// more javascripty!

	const FRIENDLY = {
	MAYBE: 'pet at your own risk',
	YES: 'ok to pet',
	NO: 'do NOT pet'
	}

	class Pet {
	constructor(name, isFriendly = FRIENDLY.MAYBE, sound = "UNKNOWN") {

bvandgrift / fix-missing.sh

Last active December 5, 2020 04:30

cheap idempotent file fetching

	#!/usr/bin/env bash

	# given a single case id (e.g., 19820427023459I) will check to see if
	# it exists in the output directory, otherwise fetch it --
	# it won't store the file if there's a problem with the request

	# usage: ./fix-missing.sh <case_id>
	if [ `ls out/${1}.html 2> /dev/null` ]; then
	exit
	else

bvandgrift / pseudo-test.rb

Last active March 20, 2019 19:19

throwaway sketch for a maybe test

	test "don't do unnecessary work for no change" do

	# let's assume that there's an enqueue(evt) method which pulls an event into the
	# processing pipeline, and that the enqueue method in turn calls a process(evt) method

	# let's further assume that if an event has an attribute, once processed, we don't want
	# to process it again for the same attribute value. so evt(attr:5), evt(attr:5), evt(attr:6) would
	# generate two process() calls, not three.

	pipeline = Pipeline.new() # or whatever

bvandgrift / keybase.md

Created November 15, 2016 00:48

keybase verification

I hereby claim:

To claim this, I am signing this object:

bvandgrift / lists.rb

Created September 1, 2016 20:51

for jason, closures

	## off the top of my head, syntax problems are an exercise for the reader

	list = [:a, 'list', 3, 1.15, {b: 'yes, really'}]

	# a simple list comprehension.
	list.each do \|thing\|
	puts thing.class # or some triviality
	end

	# functions take blocks, by default -- a block is a closure over

bvandgrift / unicat.js

Last active August 5, 2016 23:11

return an array of unique elements from an arbitrary list of arrays

	// why not let set and spread do all the work?
	// arbitrary number of arrays, unique
	function unicat(...arrays) {
	let collector = [];
	arrays.forEach((a) => {collector = collector.concat(a);});
	return Array.from(new Set(collector).values());
	}

	// O(n), i think, if concat() is implemented sanely.

bvandgrift / partials.js

Created March 31, 2016 18:46

fiddling around with the `arguments` construct in .js


	// takes a fn and a number of arguments to append to the
	// fn's argument list
	var rPartial = function(fn, extras) {
	var postArgs = [].slice.call(arguments).slice(1);
	return function(vars) {
	var preArgs = [].slice.call(arguments);
	var allArgs = preArgs.concat(postArgs);
	return fn.call(fn.this, ...allArgs);
	};

bvandgrift / attribute_requirements.rb

Created February 28, 2016 03:46

a terrible way to determine whether attrs on an ActiveRecord model are optional or required when using grape.


	module AttributeRequirements
	extend ActiveSupport::Concern

	SQL_TYPE_MATCHERS = {
	/^character varying/ => String,
	/^text/ => String,
	/^enum/ => String,
	/^timestamp/ => DateTime,
	/^integer/ => Integer,

bvandgrift / onename.txt

Created February 28, 2016 03:08

Verifying that +bvandgrift is my blockchain ID. https://onename.com/bvandgrift

bvandgrift / let-placement.clj

Created January 7, 2016 18:24

placing your peek inside of a dosync avoids potential thread conflict (from Clojure Applied forum)

	;; response to: https://forums.pragprog.com/forums/352/topics/13835

	;; this is a quick demonstration of the pitfalls in querying for a ref
	;; outside of the accompanying transaction in which you plan on changing it.

	(import '(java.util.concurrent Executors))

	;; start list
	(def slist (ref #{}))