caub

(function(){
	let scopedRule = (scope, {selectorText: selector='', cssText:css, style: {cssText}={}, styleSheet, cssRules, media}) =>
		styleSheet? // @import rules
		scopedRules(scope, styleSheet.cssRules):
		cssRules && media?  // @media rules
		`@media ${Array.from(media).join(',\n')} {${scopedRules(scope, cssRules)}}`:
		!selector||selector.startsWith(':root')||selector.startsWith('body')?
		css:
		`${selector.split(',').map(s=>`${scope} ${s}`).join(', ')} {${cssText}}`;
		//`${selector.replace(/([^,]+)/g, (_, s) => `${scope} ${s}`)} {${cssText}}`;

caub

const babel = require('babel-standalone');
const fs = require('fs');
const express = require('express');
const app = express();

app.get('/*.jsx', function(req, res){
	fs.readFile('.'+req.path, (err,data)=>{
		res.send(babel.transform(data, {presets:['react']}).code);
	});
});

caub

• Shortening const to something like ref, val, cst because

  • it's the most frequently used keyword
  • conflicts with console.log auto-completion

• null should be Object.freeze(Object.create(null)) or a special Symbol.nullable

• ([] =~= []) // true shallow compare

• ({ a: {} } =*= { a: {} }) // true deep compare

• Making function arguments flexible and coherent with arrays

caub

• dom builder examples https://jsfiddle.net/crl/tfo58xmt/5/ https://jsfiddle.net/crl/7jo9zp5t/22/
• like <input type="search"> but not https://jsfiddle.net/364Lbu1w/3/
• contenteditable https://jsfiddle.net/crl/eumxoudn/39/ react https://jsfiddle.net/crl/eumxoudn/11/
• designs address form | list | checkbox | increment buttons /5 | button | dropdown | circle nav
• fps-meter https://output.jsbin.com/banewul/
• play with unicodes https://jsfiddle.net/crl/s0xbrwv5/10/, golden ratio https://jsfiddle.net/crl/bveyL2uf/6/
• slot machine https://jsfiddle.net/crl/sbh0hrfu/
• canvas vs svg https://jsfiddle.net/crl/vbtbm83k/17/
• cancellable fetch https://jsfiddle.net/crl/8ns0abst/6/

caub

module.exports = function(gen) { // coroutine, equivalent to https://github.com/tj/co
	const it = gen();
	return Promise.resolve().then(function pump(v) {
		const next = it.next(v);
		if(next.done) return next.value;
		return Promise.resolve(next.value).then(pump, it.throw.bind(it));
	});
};

caub

Double vs Single quotes for JavaScript Strings

"foo"

• Newcomers will already be familiar with double quotes from their language. In English, we must use double quotes " to identify a passage of quoted text. If we were to use a single quote ', the reader may misinterpret it as a contraction. The other meaning of a passage of text surrounded by the ' indicates the 'colloquial' meaning. It makes sense to stay consistent with pre-existing languages, and this may likely ease the learning and interpretation of code.
• Double quotes eliminate the need to escape apostrophes (as in contraptions). Consider the string: "I'm going to the mall", vs. the otherwise escaped version: 'I'm going to the mall'.
• Double quotes mean a string. When you learn a new language like Java, Python, or C, double quotes are always used. This is because, as mentioned above, double quotes have always been used in language to indicate quoted passages of text. Old books will use double quo

caub

window.import = function (transformer) {
	const ROOT = location.origin;
	const REQUIRE_CACHE = new Map();
	const RE_EXT = /\.js\w*$/;

	function fqn(url, dirname) {
		const {href} = new URL(url.startsWith('http') ? url : (url.startsWith('/') ? ROOT : dirname) + url),
			last = href.lastIndexOf('/'), dir = href.slice(0, last+1), name = href.slice(last+1),
			filename = name ? (RE_EXT.test(name) ? name: name+'.js') : 'index.js';
		return {dir, abs: dir+filename};

caub

create table foo_version (
  id VARCHAR(32),
  v BIGINT,
  data TEXT,
  
  PRIMARY KEY (id, v)
);

create table foo (
  id VARCHAR(32),

caub

function $(container, selector) {
  const els =
    typeof selector === 'string'
      ? container.querySelectorAll(selector)
      : typeof container === 'string' ? document.querySelectorAll(container) : [container];

  const fns = {
    removeClass(...cls) {
      els.forEach(el => {
        el.classList.remove(...cls);

caub

// 2 globals defined at boot of nodejs engine
rl = cb => require('readline').createInterface({input:process.stdin}).on('line',cb);
print = console.log;

/*
Let's call an integer "repetitive" if it contains two of the same digit in a row. For example, 12232 is repetitive but 1232 is not.
Given a positive integer n < 10^15, return the number of nonrepetitive integers in [1..n].
*/
// prog
rl(s=>{r=0;d=s.length-1;for(i=0;i<=d;i++){r+=(i>0&&s[i-1]<s[i]?s[i]-1:s[i])*9**(d-i);if(s[i-1]==s[i]){r--;break}}for(i=0;i<d;i++)r+=9**i;print(r)})