spion

#!/bin/bash
# Put me in /usr/local/bin/killgrep
ps aux | egrep $1 | egrep -v '(killgrep)|(egrep)' | awk '{print $2}' | xargs kill -9

spion

function switcher() {
  var on = true;
  var self = {};
  self.wire = function(val) {
    if (on) return val;
    throw new Error('Cancelled');
  };
  self.off = function() { on = false; }
  self.on = function() { on = true; }
  return self;

spion

Software estimation Q&A

Q: What do the points mean?

A: Lets say we have two engineers, E1 and E2, estimating a story S. E1 believes the story can be done in time T1. E2 believes it can be done in time T2.

We assign the velocity numbers V1 and V2 to these two engineers, such that

spion

let Read = {};
let End = {};

function* lexer() {
  let accumulatedChars = [];
  while (true) {
    let inp = yield Read;
    if (inp === End) {
      if (accumulatedChars.length > 0) yield accumulatedChars.join('');
      return;

spion

function inRange(a: number, min: number, max: number) {
  return min <= a && a <= max;
}

class UTF8Encoder {
  bytes = new Uint8Array(4).fill(0)
  len = 0;

  toBytes(codePoint: number):void {

spion

diff --git a/frameworks/JavaScript/express/express-postgres.dockerfile b/frameworks/JavaScript/express/express-postgres.dockerfile
index f2907bd02..9b2196082 100644
--- a/frameworks/JavaScript/express/express-postgres.dockerfile
+++ b/frameworks/JavaScript/express/express-postgres.dockerfile
@@ -1,9 +1,9 @@
 FROM node:12.3.1-slim
 
-COPY ./ ./
-
+COPY package.json ./

spion

Node streams - a fractal of weird design

and a potential refactor that could fix that

This is a list of issues and confusions I've encountered with node streams, and things I wish were designed and implemented differently. If promise-streams is ever going to change to a design that doesn't build on top of node streams, this would be a list of mistakes to avoid

1. enc parameter - Why is encoding always passed together with the data? It should be a separate concern. It doesn't even make sense in objectMode
2. eventemitter base - This encourages a lot of random events to be "attached" by other authors which doesn't work. Best to have an uniform (typed) interface so that everyone knows what to expect.
3. relying on nextTick etc for execution order - This is very unreliable and causes all sorts of unpredictable rules for implementers which are not documented anywhere. When you attach listeners determines what will happen.
4. no error propagation - we need the

spion

@observer class Chart(props) {
  @computed get data() { return getDataWithinRange(this.props.dateRange) }
  @computed get dimensions() { return getDimensions() }
  @computed get xScale() { return getXScale() }
  @computed get yScale() { return getYScale() }
  render() { 
    // use this.xScale, this.yScale etc. component will re-render automatically if any of those update.
    return <svg className="Chart" /> 
}

spion

Be careful when feature flags affect any shared mutable state. This for example will cause data loss if the flag value changes during the work:

this.fancyModel = FancyModel.createInitial()
this.rustyModel = RustyModel.createInitial()

async loadData() { 
  let flag = await this.ff.isEnabled('flag');
  let data = await this.fetchData();

spion

type ExtractValuesRecusrively<T> = T extends FormState<infer U>
  ? { [K in keyof U]: ExtractValuesRecusrively<U[K]> }
  : T extends FieldState<infer V>
  ? V
  : never;

// vs

type ExtractValuesRecusrively<State> = State extends FormState<infer InnerForm>
  ? { [FieldKey in keyof InnerForm]: ExtractValuesRecusrively<InnerForm[FieldKey]> }