Swift

Question 1

What is a nil value?

Answer 1

Nothing

Question 2

What is the purpose of nil?

Answer 2

Used to represent the absence of a value.

Question 3

Can ints be assigned to nil?

Answer 3

False

Question 4

Can ints be assigned to objects?

Answer 4

False

Question 5

What is a function?

Answer 5

Self contained chucks of code that performs a specific task.

Question 6

Do you give a name to a function to be called upon?

Answer 6

Yes

Question 7

What is a method?

Answer 7

Functions that are associated with a particular type.

Question 8

What are some instance methods in swift?

Answer 8

Classes, structures, and enumerations because they all encapsulate a specific task.

Question 9

What is a syntax?

Answer 9

Specific rules and symbols that are considered correctly structured in code.

Question 10

Does every function in swift have a type?

Answer 10

True

Question 11

What is a return statement?

Answer 11

Tells the program to return to the original address.

Question 12

What is () called?

Answer 12

Placeholder

Question 13

What does a if/else statement do?

Answer 13

If a condition is met execute the code else execute the second line of code.

Question 14

> , =, <=

These are examples of what kind of operators?

Answer 14

Comparison Operators

Question 15

What is an instance?

Answer 15

A var defined in a class.

Question 16

What is nesting?

Answer 16

Loops that contain other loops.

Question 17

What does % 2 == 0 do?

Answer 17

Tests evenness.

Question 18

What does % 2 == 1 do?

Answer 18

Tests oddness.

Question 19

What does sum do?

Answer 19

Causes the playground to print a total sum.

Question 20

Are dictionaries ordered or unordered?

Answer 20

Unordered

Question 21

What are dictionaries?

Answer 21

You type in a key (keyword) and the program returns a value.

Question 22

What is initialization?

Answer 22

The process of preparing an instance, class, structure, enumeration for use.

Question 23

What is … ?

Answer 23

A closed range operator.

Question 24

What is hashable?

Answer 24

A special function that can change each key into a integer.

Question 25

Are ranges hashable?

Answer 25

No

Question 26

How do you unwrap an optional?

Answer 26

if let statement

Question 27

What does the import keyword do?

Answer 27

Accesses code that is written in the framework.

Question 28

Bundles of code specialized for a certain purpose that we can use in our projects

Answer 28

Framework

Question 29

What is a Plist?

Answer 29

Property’s List is apples own data format that makes it easy to store simple data like numbers, strings, and truth values

Question 30

What is JSON?

Answer 30

Short form “JavaScript Object Notation” uses data to communicate between devices.

Question 31

What is a Key in Plist?

Answer 31

A unique string that identifies a value (unless an array is specified)

Question 32

What is a Type in Plist?

Answer 32

A type of value that exists in a key.

Question 33

What is a value in Plist?

Answer 33

The value that exists in the key.

Question 34

A way for us to covert an object of one type to another type.

Answer 34

Conditional Downcasting

Question 35

Will the conversion of a downcast fail of the literal value in the Plist is not the one you specified?

Answer 35

Yes

Question 36

What does

let declaration = Bundle.main.url(forResource: String, withExtension: String)!

do?

Answer 36

Starts extraction of the Plist data

Question 37

What does 
let studentsDictionary = NSDictionary(contentsOfURL: studentsPlist) as! [String:Any] 
do?

Answer 37

Convert the Plist dictionary to a swift type dictionary.

Question 38

What does

if let shawn = studentsDictionary["Shawn"] as? [String:Any] {
    // continue extracting values...
}

do?

Answer 38

Convert each student item into it’s own dictionary type.

Question 39

How are JSON arrays specified?

Answer 39

By brackets. []

Question 40

What are JSON objects specified with?

Answer 40

Curly braces {}.

Question 41

What is key: value syntax?

Answer 41

Key-Value pair.

Question 42

What is key: value syntax?

Answer 42

Key-Value pair.