Picturing Programs. An Introduction to Computer Programming (Racket / Scheme / Lisp)

Contents......Page 2
Intro......Page 10
Working with pictures......Page 16
Manipulating pictures......Page 17
Making mistakes......Page 20
More complex manipulations......Page 23
Saving Your Work: the Definitions pane......Page 25
Working through nested expressions: the Stepper......Page 26
Syntax and box diagrams......Page 27
Review of important words and concepts......Page 30
Reference: functions that work on images......Page 31
Defining a variable......Page 32
What’s in a name?......Page 34
More syntax rules......Page 35
Reference: functions for defining variables......Page 36
Other kinds of arguments......Page 37
Creating simple shapes......Page 40
Data types and contracts......Page 42
More functions on pictures......Page 47
Specifying results and checking your work......Page 52
Reading and writing images......Page 53
Review of important words and concepts......Page 54
Reference: Built-in functions for images......Page 55
Defining your own functions......Page 57
What’s in a definition?......Page 59
Parameters and arguments......Page 61
Parameters, arguments, and the Stepper......Page 62
Testing a Function Definition......Page 64
A new syntax rule......Page 68
Scope and visibility......Page 70
An analogy from English......Page 71
Review of important words and concepts......Page 73
Reference: Built-in functions for defining and testing functions......Page 74
A more detailed recipe......Page 75
Function contracts and purpose statements......Page 76
Examples (also known as Test Cases)......Page 79
Common beginner mistakes......Page 81
Checking syntax......Page 84
The inventory......Page 85
Inventories with values......Page 88
The function body......Page 89
Using the function......Page 92
Putting it all together......Page 93
Review of important words and concepts......Page 94
Reference......Page 95
Preliminaries......Page 96
Tick handlers......Page 97
Common beginner mistakes......Page 98
Writing tick handlers......Page 100
Writing draw handlers......Page 102
Other kinds of event handlers......Page 104
Design recipe for an animation, first version......Page 110
A note on syntax......Page 111
Review of important words and concepts......Page 112
Reference: Built-in functions for animation......Page 113
Fitting arithmetic into Racket syntax......Page 114
Variables and numbers......Page 115
Why prefix notation is your friend......Page 117
Converting from infix to prefix......Page 118
Kinds of numbers......Page 120
Contracts for built-in arithmetic functions......Page 121
Writing numeric functions......Page 122
Manipulating colors in images......Page 130
Randomness......Page 136
Reference: Built-in functions on numbers......Page 139
Model and view......Page 141
Design recipe for an animation, second version......Page 143
Animations using......Page 145
Animations with other numeric functions......Page 147
Randomness in animations......Page 150
Reference......Page 151
Operations......Page 152
String variables and functions......Page 153
Reference: Built-in functions on strings......Page 154
Design recipe for Animation, version 3......Page 156
Reference......Page 159
Re-using variables......Page 160
Composing functions......Page 164
Designing for re-use......Page 166
Designing multi-function programs: a case study......Page 167
Practicalities of multi-function programs......Page 178
Re-using definitions from other files......Page 179
Review of important words and concepts......Page 181
Reference......Page 182
Definition by Choices......Page 183
Defining new Types......Page 184
Comparing strings......Page 186
Comparing numbers......Page 188
Designing functions involving booleans......Page 191
Testing types......Page 192
Boolean operators......Page 193
Review of important words and concepts......Page 197
Reference: Functions involving Booleans......Page 198
Stopping animations......Page 199
Stopping in response to events......Page 202
Review of important words and concepts......Page 203
Reference: Built-in functions for making deci- sions in animations......Page 205
Making decisions......Page 206
Else and error-handling......Page 209
Design recipe for functions that make decisions......Page 210
Case study: bank interest......Page 213
Ordering cases in a conditional......Page 216
Unnecessary conditionals......Page 218
Nested conditionals......Page 220
Decisions among data types......Page 224
Review of important words and concepts......Page 227
Reference: Built-in functions for making deci- sions......Page 228
Inventories and templates......Page 229
Outventories and templates......Page 233
Review of important words and concepts......Page 234
Reference......Page 236
String decisions......Page 237
Numeric decisions......Page 243
Reference: New Functions......Page 244
Mouse handlers......Page 245
Key handlers......Page 248
Key release......Page 251
Reference: Built-in functions for mouse and key handling......Page 252
Error messages......Page 253
Testing for errors......Page 254
Review of important words and concepts......Page 255
Reference: Built-in functions for signaling and testing errors......Page 256
Definition by Parts......Page 257
data type......Page 258
s......Page 260
s......Page 261
s......Page 265
s......Page 267
Colors......Page 272
Reference: Built-in functions on posns and colors......Page 274
Why and how......Page 276
A Recipe for Defining a Struct......Page 279
Exercises on Defining Structs......Page 281
Writing functions on user-defined structs......Page 282
Functions returning user-defined structs......Page 284
Animations using user-defined structs......Page 286
Structs containing other structs......Page 292
Decisions on types, revisited......Page 294
Review of important words and concepts......Page 299
Reference: Built-in functions for defining struc- tures......Page 300
Definition by Self-reference......Page 301
What is a list?......Page 302
Defining lists in Racket......Page 303
The way we really do lists......Page 312
Lots of functions to write on lists......Page 320
Lists of structs......Page 327
Strings as lists......Page 332
Arbitrarily nested lists......Page 334
Review of important words and concepts......Page 335
Reference: Built-in functions on lists......Page 336
Doing something to each element......Page 337
Making decisions on each element......Page 339
A shorter notation for lists......Page 341
Strings as lists......Page 343
More complex functions involving lists......Page 345
Review of important words and concepts......Page 346
Reference: built-in functions that return lists......Page 347
What is a whole number?......Page 348
Different base cases, different directions......Page 355
Peano arithmetic......Page 357
The wholes in binary......Page 360
Reference: Built-in functions on whole numbers......Page 366
Separable parameters......Page 367
Synchronized parameters......Page 368
Interacting parameters......Page 370
Exercises......Page 374
Review of important words and concepts......Page 378
Reference......Page 379
Miscellaneous topics......Page 380
Timing function calls......Page 381
Review of important words and concepts......Page 382
Reference: New syntax for timing......Page 383
Using locals for efficiency......Page 384
Using locals for clarity......Page 387
Using locals for information-hiding......Page 388
Using locals to insert parameters into functions......Page 391
Reference: New syntax for local definitions......Page 394
Adding parameters......Page 395
Functions as parameters......Page 396
Functions returning lists......Page 401
Choosing a winner......Page 403
Accumulating over a list......Page 404
Anonymous functions......Page 405
Functions in variables......Page 406
Functions returning functions......Page 407
Sequences and series......Page 410
Reference: higher-order and anonymous func- tions......Page 413
Input, Output & Sequence......Page 415
The symbol data type......Page 416
Console output......Page 417
Sequential programming......Page 420
Console input......Page 424
Input streams......Page 426
Files......Page 430
Review of important words and concepts......Page 431
Reference: input, output, and sequence......Page 432
Remembering changes......Page 433
Mutating variable values......Page 434
Memoization......Page 437
Static and dynamic scope......Page 440
Encapsulating state......Page 441
Mutating structures......Page 444
Reference: Built-in functions for mutation and assignment......Page 447
Next Steps......Page 448
Index......Page 450
Biblio......Page 455