People can “learn to code” on so many websites, in little in-browser environments. Sites instruct on the basics of ‘for’ loops and ‘if’ statements. In advanced courses, learn algorithms and data structures. Writing toy programs is eminently teachable. Writing useful programs is something else. And writing them well is a mysterious art. Greg Wilson‘s new … Read moreBook Review: Software Design By Example
TL;DR: startSpan is easier and measures a duration. Use it if your work won’t create any subspans. startActiveSpan requires that you pass a callback for the work in the span, and then any spans created during that work will be children of this active span. I’m instrumenting a Node.js app with OpenTelemetry, and adding some … Read morestartSpan vs startActiveSpan in OpenTelemetry JS
Today, I found a bug before I noticed it. Like, it was subtle, and so I wasn’t quite sure I saw it–maybe I hadn’t hit refresh yet? Later, I looked at the trace of my function and boom, there was a clear bug. Here’s the function with the bug. It responds to a request to … Read moreTracing makes a bug easy to spot
Sometimes the obvious, default API is never what you want. That’s when you have to memorize the “do things right” flag. For yargs, the command-line argument parser for Node.js, specify options and subcommands like this: There. Next time I can cut and paste this instead of scouring the internet for how to make yargs do … Read moreyargs –do-things-right
import * as fs from “fs”; import { promisify } from “util”; const content: Promise<string> = promisify(fs.readFile)(“path/to/the/file”, { encoding: “UTF-8” }) I am tired of looking that up over and over every time I want to read a file into a promise in Node using TypeScript, so here it is. Next time, bring me here, Google. The promisify call turns fs.readFile from a callback-based method to a promise-based one. promisify accepts … Read moreRead a file with promises in TypeScript on Node
Karl Popper defines rationality as: basing beliefs on logical arguments and evidence. Irrationality is everything else. He also defines comprehensive rationality as: only logical arguments and evidence are valid basis for belief. But this belief itself can only be accepted by choice or faith, so comprehensive rationality is self-contradictory. It also excludes a lot of … Read moreIn defense of rationality and dynamic programming
A few hundred years ago, we decided that circular causality was a logical fallacy. All causes are linear. If something moves, then something else pushed it. If you want to see why, you have to look smaller; all forces derive from microscopic forces. Yet as a human, I see circular causality everywhere. autocatalytic loops in … Read moreGrowth Loops: circular causality is real
It’s all that THAT Conference is not THOSE conferences. It’s about the developer as more than a single unit: this year, in multiple ways. I talked about our team as a system — more than a system, a symmathesy. Cory House said that if you want to change your life, change your systems. As humans, our greatest power … Read moreSystems and context at THAT Conference
Lately I’ve been wrestling with npm. Here are some rules I’ve learned: Use `npm ci` rather than `npm install` `npm ci` will bring down exactly the dependencies specified in package-lock.json. `npm install` does more than that; it also tries to update some libraries to a more recent version. Sometimes it updates URLs or nonsense in … Read moreDo Things Right with npm install
TL;DR: creating a Promise splits off another path of execution, and the Promise object represents the end of that path. Calling .then adds code to the end of that path. You can think of your program’s execution as following a piece of yarn. this video illustrates the difference between a synchronous program and the same program … Read moreUnderstanding Promises in JavaScript (with yarn and Legos)