Essential TypeScript From Beginner to Pro

Table of Contents......Page 5
About the Author......Page 19
About the Technical Reviewer......Page 20
Part I: Getting Started with TypeScript......Page 21
Step 2: Install Git......Page 22
Step 4: Install a Programmer’s Editor......Page 23
Initializing the Project......Page 24
Compiling and Executing the Code......Page 25
Defining the Data Model......Page 26
Creating the Todo Item Collection Class......Page 28
Checking the Basic Data Model Features......Page 29
Adding Features to the Collection Class......Page 32
Providing Access to To-Do Items......Page 33
Removing Completed Tasks......Page 35
Providing Item Counts......Page 36
Using a Third-Party Package......Page 39
Adding Type Declarations for the JavaScript Package......Page 41
Adding Commands......Page 42
Filtering Items......Page 43
Adding Tasks......Page 44
Marking Tasks Complete......Page 46
Persistently Storing Data......Page 49
Applying the Persistent Collection Class......Page 51
Summary......Page 52
Understanding the TypeScript Developer Productivity Features......Page 53
Understanding the JavaScript Version Features......Page 54
What Is the Structure of This Book?......Page 55
Are There Lots of Examples?......Page 56
Summary......Page 58
Preparing for This Chapter......Page 59
Getting Confused by JavaScript......Page 60
Understanding JavaScript Types......Page 61
Working with Primitive Data Types......Page 62
Understanding Type Coercion......Page 64
Avoiding Unintentional Type Coercion......Page 65
Appreciating the Value of Explicitly Applied Type Coercion......Page 66
Working with Functions......Page 67
Avoiding Argument Mismatch Problems......Page 68
Using Arrow Functions......Page 71
Working with Arrays......Page 72
Working with Objects......Page 74
Adding, Changing, and Deleting Object Properties......Page 75
Guarding Against Undefined Objects and Properties......Page 76
Using the Spread and Rest Operators on Objects......Page 77
Defining Getters and Setters......Page 79
Defining Methods......Page 80
Understanding the this Keyword......Page 82
Understanding the this Keyword in Stand-Alone Functions......Page 83
Understanding this in Methods......Page 84
Understanding this in Arrow Functions......Page 86
Returning to the Original Problem......Page 88
Summary......Page 89
Preparing for This Chapter......Page 90
Understanding JavaScript Object Inheritance......Page 91
Inspecting and Modifying an Object’s Prototype......Page 92
Creating Custom Prototypes......Page 94
Using Constructor Functions......Page 95
Chaining Constructor Functions......Page 96
Checking Prototype Types......Page 98
Defining Static Properties and Methods......Page 99
Using JavaScript Classes......Page 100
Using Inheritance in Classes......Page 101
Defining Static Methods......Page 102
Using Iterators and Generators......Page 103
Using a Generator......Page 104
Defining Iterable Objects......Page 106
Storing Data by Key Using an Object......Page 108
Using Symbols for Map Keys......Page 110
Storing Data by Index......Page 112
Creating a JavaScript Module......Page 113
Using a JavaScript Module......Page 114
Exporting Named Features from a Module......Page 115
Defining Multiple Named Features in a Module......Page 117
Summary......Page 118
Preparing for This Chapter......Page 119
Understanding the Project Structure......Page 120
Using the Node Package Manager......Page 121
Understanding the TypeScript Compiler Configuration File......Page 124
Compiling TypeScript Code......Page 126
Understanding Compiler Errors......Page 127
Using Watch Mode and Executing the Compiled Code......Page 128
Automatically Executing Code After Compilation......Page 130
Using the Version Targeting Feature......Page 131
Setting the Library Files for Compilation......Page 133
Selecting a Module Format......Page 136
Useful Compiler Configuration Settings......Page 139
Summary......Page 141
Preparing for This Chapter......Page 142
Adding Breakpoints......Page 143
Using Visual Studio Code for Debugging......Page 144
Using the Integrated Node.js Debugger......Page 145
Using the Remote Node.js Debugging Feature......Page 146
Using the TypeScript Linter......Page 148
Disabling Linting Rules......Page 150
Unit Testing TypeScript......Page 152
Creating Unit Tests......Page 153
Starting the Test Framework......Page 154
Summary......Page 156
Part II: Working with TypeScript......Page 157
Chapter 7: Understanding Static Types......Page 158
Preparing for This Chapter......Page 159
Understanding Static Types......Page 161
Creating a Static Type with a Type Annotation......Page 163
Using Implicitly Defined Static Types......Page 164
Using the any Type......Page 167
Disabling Implicit Any Types......Page 169
Using Type Unions......Page 170
Using Type Assertions......Page 172
Asserting to an Unexpected Type......Page 174
Using a Type Guard......Page 175
Using the unknown Type......Page 177
Using Nullable Types......Page 179
Restricting Nullable Assignments......Page 180
Removing null from a Union with an Assertion......Page 181
Using the Definite Assignment Assertion......Page 183
Summary......Page 185
Chapter 8: Using Functions......Page 186
Preparing for This Chapter......Page 187
Redefining Functions......Page 188
Understanding Function Parameters......Page 190
Using Optional Parameters......Page 191
Using a Parameter with a Default Value......Page 192
Using a Rest Parameter......Page 193
Applying Type Annotations to Function Parameters......Page 194
Controlling Null Parameter Values......Page 195
Understanding Function Results......Page 196
Disabling Implicit Returns......Page 197
Using Type Annotations for Function Results......Page 198
Overloading Function Types......Page 199
Summary......Page 201
Chapter 9: Using Arrays, Tuples, and Enums......Page 202
Preparing for This Chapter......Page 203
Working with Arrays......Page 204
Using Inferred Typing for Arrays......Page 206
Avoiding Problems with Inferred Array Types......Page 207
Understanding the never Array Type Pitfall......Page 208
Working with Tuples......Page 209
Processing Tuples......Page 210
Using Tuple Types......Page 211
Using Enums......Page 212
Understanding How Enums Work......Page 213
Using Specific Enum Values......Page 214
Using String Enums......Page 216
Understanding the Value-Checking Limitation......Page 217
Using Constant Enums......Page 218
Using Literal Value Types......Page 220
Using Literal Value Types in Functions......Page 221
Mixing Value Types in a Literal Value Type......Page 222
Using Overrides with Literal Value Types......Page 223
Using Type Aliases......Page 224
Summary......Page 225
Chapter 10: Working with Objects......Page 226
Preparing for This Chapter......Page 227
Working with Objects......Page 228
Using Object Shape Type Annotations......Page 229
Understanding How Shape Types Fit......Page 230
Including Methods in Shape Types......Page 231
Enforcing Strict Checking for Methods......Page 233
Dealing with Excess Properties......Page 234
Using Shape Type Unions......Page 236
Understanding Union Property Types......Page 237
Type Guarding by Checking Properties......Page 238
Type Guarding with a Type Predicate Function......Page 241
Using Type Intersections......Page 242
Using Intersections for Data Correlation......Page 244
Understanding Intersection Merging......Page 245
Merging Properties with Different Types......Page 247
Merging Methods......Page 250
Summary......Page 252
Chapter 11: Working with Classes and Interfaces......Page 253
Preparing for This Chapter......Page 254
Using Constructor Functions......Page 255
Using Classes......Page 257
Using the Access Control Keywords......Page 259
Defining Read-Only Properties......Page 262
Simplifying Class Constructors......Page 263
Using Class Inheritance......Page 264
Understanding Type Inference for Subclasses......Page 265
Using an Abstract Class......Page 267
Type Guarding an Abstract Class......Page 269
Using Interfaces......Page 270
Implementing Multiple Interfaces......Page 272
Extending Interfaces......Page 274
Defining Optional Interface Properties and Methods......Page 276
Defining an Abstract Interface Implementation......Page 278
Type Guarding an Interface......Page 279
Dynamically Creating Properties......Page 281
Summary......Page 282
Chapter 12: Using Generic Types......Page 283
Preparing for This Chapter......Page 284
Understanding the Problem......Page 285
Adding Support for Another Type......Page 286
Creating Generic Classes......Page 287
Using Different Type Arguments......Page 289
Constraining Generic Type Values......Page 290
Constraining Generic Types Using a Shape......Page 292
Defining Multiple Type Parameters......Page 294
Applying a Type Parameter to a Method......Page 295
Allowing the Compiler to Infer Type Arguments......Page 296
Adding Extra Features to the Existing Type Parameters......Page 298
Fixing the Generic Type Parameter......Page 299
Restricting the Generic Type Parameter......Page 300
Type Guarding Generic Types......Page 302
Defining a Static Method on a Generic Class......Page 304
Defining Generic Interfaces......Page 306
Passing on the Generic Type Parameter......Page 307
Creating an Abstract Interface Implementation......Page 309
Summary......Page 311
Chapter 13: Advanced Generic Types......Page 312
Preparing for This Chapter......Page 313
Using Generic Collections......Page 314
Using Generic Iterators......Page 316
Combining an Iterable and an Iterator......Page 318
Creating an Iterable Class......Page 319
Using the Index Type Query......Page 320
Explicitly Providing Generic Type Parameters for Index Types......Page 321
Using the Indexed Access Operator......Page 322
Using an Index Type for the Collection Class......Page 324
Using Type Mapping......Page 326
Using a Generic Type Parameter with a Mapped Type......Page 327
Changing Property Optionality and Mutability......Page 328
Mapping Specific Properties......Page 330
Creating Types with a Type Mapping......Page 331
Using Conditional Types......Page 332
Using Conditional Types in Generic Classes......Page 334
Using Conditional Types with Type Unions......Page 336
Using Conditional Types in Type Mappings......Page 337
Identifying Properties of a Specific Type......Page 338
Inferring Additional Types in Conditions......Page 340
Inferring Types of Functions......Page 342
Summary......Page 343
Chapter 14: Working with JavaScript......Page 344
Preparing for This Chapter......Page 345
Adding the TypeScript Code to the Example Project......Page 346
Working with JavaScript......Page 349
Including JavaScript in the Compilation Process......Page 350
Type Checking JavaScript Code......Page 351
Describing Types Used in JavaScript Code......Page 353
Using Comments to Describe Types......Page 354
Using Type Declaration Files......Page 355
Describing Third-Party JavaScript Code......Page 358
Using Definitely Typed Declaration Files......Page 361
Using Packages That Include Type Declarations......Page 363
Generating Declaration Files......Page 365
Summary......Page 368
Part III: Creating Web Applications......Page 369
Preparing for This Chapter......Page 370
Adding a Bundler......Page 372
Adding a Development Web Server......Page 375
Creating the Data Model......Page 378
Creating the Data Source......Page 379
Rendering HTML Content Using the DOM API......Page 382
Adding Support for Bootstrap CSS Styles......Page 383
Using JSX to Create HTML Content......Page 385
Understanding the JSX Workflow......Page 386
Configuring the TypeScript Compiler and the Webpack Loader......Page 388
Creating the Factory Function......Page 389
Using the JSX Class......Page 390
Importing the Factory Function in the JSX Class......Page 391
Displaying a Filtered List of Products......Page 392
Displaying Content and Handling Updates......Page 396
Summary......Page 398
Preparing for This Chapter......Page 399
Adding a Web Service......Page 402
Incorporating the Data Source into the Application......Page 403
Using Decorators......Page 405
Using Decorator Metadata......Page 407
Adding an Order Details Class......Page 411
Completing the Application......Page 413
Adding the Production HTTP Server Package......Page 417
Creating the Server......Page 418
Using Relative URLs for Data Requests......Page 419
Building the Application......Page 420
Testing the Production Build......Page 421
Creating the Docker Container......Page 422
Running the Application......Page 423
Summary......Page 425
Chapter 17: Creating an Angular App, Part 1......Page 426
Configuring the Web Service......Page 427
Configuring the Bootstrap CSS Package......Page 429
Starting the Example Application......Page 430
Understanding TypeScript in Angular Development......Page 431
Understanding the TypeScript Angular Toolchain......Page 432
Understanding the Two Angular Compilers......Page 433
Creating the Data Model......Page 436
Creating the Data Source......Page 437
Creating the Data Source Implementation Class......Page 439
Displaying a Filtered List of Products......Page 441
Displaying the Category Buttons......Page 443
Combining the Product, Category, and Header Components......Page 445
Configuring the Application......Page 447
Summary......Page 449
Chapter 18: Creating an Angular App, Part 2......Page 450
Preparing for This Chapter......Page 451
Completing the Example Application Features......Page 452
Adding the Summary Component......Page 454
Creating the Routing Configuration......Page 455
Adding the Production HTTP Server Package......Page 457
Creating the Server......Page 458
Using Relative URLs for Data Requests......Page 459
Building the Application......Page 460
Testing the Production Build......Page 461
Preparing the Application......Page 462
Creating the Docker Container......Page 463
Running the Application......Page 464
Summary......Page 465
Chapter 19: Creating a React App......Page 466
Configuring the Web Service......Page 467
Installing the Bootstrap CSS Package......Page 468
Starting the Example Application......Page 469
Understanding TypeScript in React Development......Page 470
Defining the Entity Types......Page 473
Displaying a Filtered List of Products......Page 474
Using a Functional Component and Hooks......Page 476
Displaying a List of Categories and the Header......Page 478
Composing and Testing the Components......Page 479
Creating the Data Store......Page 482
Creating the HTTP Request Class......Page 485
Connecting the Data Store to the Components......Page 486
Summary......Page 489
Chapter 20: Creating a React App, Part 2......Page 490
Preparing for This Chapter......Page 491
Configuring URL Routing......Page 492
Adding the Order Summary Component......Page 494
Adding the Confirmation Component......Page 496
Completing the Routing Configuration......Page 497
Adding the Production HTTP Server Package......Page 498
Creating the Server......Page 499
Using Relative URLs for Data Requests......Page 500
Building the Application......Page 501
Testing the Production Build......Page 502
Creating the Docker Container......Page 503
Running the Application......Page 504
Summary......Page 506
Chapter 21: Creating a Vue.js App, Part 1......Page 507
Preparing for This Chapter......Page 508
Configuring the Web Service......Page 509
Starting the Example Application......Page 510
Understanding the TypeScript Vue.js Toolchain......Page 512
Creating the Entity Classes......Page 514
Displaying a Filtered List of Products......Page 515
Displaying a List of Categories and the Header......Page 517
Composing and Testing the Components......Page 519
Creating the Data Store......Page 522
Creating Data Store Decorators......Page 524
Connecting Components to the Data Store......Page 525
Adding Support for the Web Service......Page 527
Summary......Page 531
Chapter 22: Creating a Vue.js App, Part 2......Page 532
Preparing for This Chapter......Page 533
Configuring URL Routing......Page 534
Completing the Example Application Features......Page 536
Adding the Order Summary Component......Page 537
Adding the Confirmation Component......Page 538
Completing the Routing Configuration......Page 539
Adding the Production HTTP Server Package......Page 540
Creating the Server......Page 541
Using Relative URLs for Data Requests......Page 542
Testing the Production Build......Page 543
Preparing the Application......Page 544
Creating the Docker Container......Page 545
Running the Application......Page 546
Summary......Page 547
Index......Page 548