LEARNING JAVASCRIPT - Trang 12

Functions as…Functions 185

So What? 187

Functions Are Objects 188

IIFEs and Asynchronous Code 189

Function Variables 191

Functions in an Array 193

Pass a Function into a Function 194

Return a Function from a Function 195

Recursion 196

Conclusion 197

14.

Asynchronous Programming. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199

The Analogy 200

Callbacks 200

setInterval and clearInterval 201

Scope and Asynchronous Execution 202

Error-First Callbacks 203

Callback Hell 204

Promises 205

Creating Promises 206

Using Promises 206

Events 208

Promise Chaining 210

Preventing Unsettled Promises 211

Generators 212

One Step Forward and Two Steps Back? 215

Don’t Write Your Own Generator Runner 216

Exception Handling in Generator Runners 216

Conclusion 217

15.

Date and Time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219

Dates, Time Zones, Timestamps, and the Unix Epoch 219

Constructing Date Objects 220

Moment.js 221

A Practical Approach to Dates in JavaScript 222

Constructing Dates 222

Constructing Dates on the Server 222

Constructing Dates in the Browser 223

Transmitting Dates 223

Displaying Dates 224

Date Components 225

Comparing Dates 226

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