toddmantell

//Examples of JS Object.freeze function (mdn: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/freeze)
let o = {
  name: 'todd',
  age: 34,
  favoriteLanguage: 'JavaScript'
};

Object.freeze(o);

o.newProp = 'this should not get added';

toddmantell

//JavaScript Objects and Prototypes: Two ways of understanding prototypes

//Constructor function
function Cat(name, color) {
    this.name = name;
    this.color = color;
    //this.age = 7;
}

console.log(Cat.prototype);

toddmantell

// Original logic for reference:
    component ? ( // component prop gets first priority, only called if there's a match
       match ? React.createElement(component, props) : null
    ) : render ? ( // render prop is next, only called if there's a match
       match ? render(props) : null
     ) : children ? ( // children come last, always called
      typeof children === 'function' ? (
        children(props)
       ) : !Array.isArray(children) || children.length ? ( // Preact defaults to empty children array
         React.Children.only(children)

toddmantell

const baseArray = [1, 2, 3, 4];

const newArr = Object.assign([...baseArray], {2: 5});

console.log(newArr); // [1, 2, 5, 4]

toddmantell

export default function () {  
  return {
    visitor: {
      VariableDeclaration(path) {
    	path.node.declarations[0].id.name = 'TransformedInVariableDeclaration';
        const template = path.node.declarations[0].init.quasis[0].value.raw;
        console.log(template);
      },
      TemplateLiteral(path) {
        const template = path.node.quasis[0].value.raw;

toddmantell

//copy this into AST Explorer and run it against a standard import statement, like import React from 'react';

export default function ({types: t}) {
  return {
    visitor: {
		ImportDeclaration(path) {
          const {node} = path;
        	path.replaceWith(
            	t.variableDeclaration('var', [
                	t.variableDeclarator(t.identifier(`_${node.specifiers[0].local.name}`),

toddmantell

//Should transform: import {Component} from 'react';
//to: const _Component = require('react').Component;

export default function ({types: t}) {
  return {
    visitor: {
	ImportDeclaration(path) {
          const {node} = path;
        	path.replaceWith(
            	t.variableDeclaration('var', 

toddmantell

/*Object.create() vs new constructor(): constructor will have __proto__ and a "prototype" property, but a regular object will only have __proto__*/

//Object.create() just creates a new object and assigns it the prototype that you provide as the first argument
const person = {
  name: 'Name',
  age: 100,
  sayHello: function () {
    console.log(`Hello, my name is ${this.name} and I am ${this.age} years old`);
  }
};

toddmantell

const numbers = [1,2,3,4,5,6,7,8];

Array.prototype.logValues = function() {
  for (i = 0; i < this.length; i++) {
    console.log(this[i]);
  }
};

numbers.logValues();

toddmantell

{
    "editor.wrappingColumn": 0,
    "typescript.check.tscVersion": false,
    "workbench.colorTheme": "Operator Mono Dark Theme",
    "editor.tabSize": 2,
    "workbench.iconTheme": "vscode-icons",
    "[javascript]": { "editor.tabSize": 2, "editor.insertSpaces": false, "editor.detectIndentation": false }
}