toboid

var handlers = [];

handlers.push(function(next) {
  console.log ('first handler');
  next();
});

handlers.push(function(next) {
  console.log ('second handler');
  next();

toboid

var Promise = require('promise');

// Step 1 fails and rejects it's promise
function step1() {
  return new Promise(function(resolve, reject) {
    reject('Something went wrong');
  });
}
 
// Step 2 doesn't do anything to handle error

toboid

const {promisify} = require('util');
const fs = require('fs');
const readFile = promisify(fs.readFile);

readFile('./foo.txt').then(
    fileContents => console.log(fileContents.toString()),
    error => console.error(error)
);

toboid

const {promisify} = require('util');
const fs = require('fs');
const readFile = promisify(fs.readFile);

// await can only be used within an async function
(async () => {
    try {
        const fileContents = await readFile('./foo.txt');
        console.log(fileContents.toString());
    } catch (ex) {

toboid

const {promisify} = require('util');
const child = require('child_process');
const exec = promisify(child.exec);

exec('echo "Hello world"').then(
    result => console.log(result), // Prints { stdout: 'Hello world\n', stderr: '' }
    error => console.error(error)
);

toboid

nvm_global () {
    PKG_NAME=$1
    VERSIONS=()

    I=0
    for VER in $(nvm_ls)
    do
        nvm exec --silent ${VER} npm ls -g ${PKG_NAME} --depth=0 >/dev/null 2>&1

        if [ $? -eq 0 ]; then

toboid

const assert = require('assert');
const fs = require('fs');
const libxmljs = require('libxmljs');

// Read the sitemap and schema from the file system
// Could just as easily get these over HTTP
const sitemap = fs.readFileSync('../sitemap.xml');
const schema = fs.readFileSync('./schemas/sitemap.xsd');

// Parse the sitemap and schema

toboid

<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema ...>
    <xsd:import
        namespace="http://www.google.com/schemas/sitemap-news/0.9"
        schemaLocation="./test/schemas/sitemap-news.xsd"/>

    ...
</xsd:schema>

toboid

const orderCounts = [3, 34, 15, 55, 6, 7];

const mean = sample => sample.reduce((sum, x) => sum + x, 0) / sample.length;
const square = x => x * x;
const difference = x => y => x - y;
const variance = sample => mean(sample.map(difference(mean(sample))).map(square));

// Variance
const σ2 = variance(orderCounts);
// Standard deviation

toboid

function pipe (...funcs) {
    if (!funcs.length) {
        throw new Error('pipe requires at least 1 argument');
    }
    
    return (...args) => funcs.slice(1).reduce((accum, func) => func(accum), funcs[0](...args))
}

// Usage
pipe((a, b) => a + b)(1, 2); // => 3