Section 12 - Functional programming

Question 1

What is a programming paradigm?

Answer 1

A style of computer programming

Question 2

What are the 4 types of programming paradigms?

Answer 2

• Procedural programming
• Object-orientated programming
• Declarative programming
• Functional programming

Question 3

What is procedural programming?

Answer 3

Where a series of instructions tells the computer what to do with the input in order to solve the problem

Question 4

What is structured programming?

Answer 4

A form of procedural programming which uses the modular techniques to split large programs into manageable chunks

Question 5

What programming constructs does structured programming use?

Answer 5

• Sequence
• Selection
• Iteration
• Recursion

Question 6

What is object-orientated programming?

Answer 6

A programming paradigm comprised of classes of objects. It is was developed to make it possible to abstract details of implementation away from the user, making code reusable and programs easy to maintain

Question 7

What is declarative programming?

Answer 7

Where you write statements the describe the problem to be solved, with the language implementation deciding the best way to solve it

Question 8

What is functional programming?

Answer 8

Functions are used as the fundamental building blocks of a program, where statements are written as a series of functions which accept input data as arguments and return an output

Question 9

What is a function?

Answer 9

A mapping from the domain to the co-domain

Question 10

What is the domain?

Answer 10

The set of inputs

Question 11

What is the co-domain?

Answer 11

The set of possible outputs

Question 12

What is always true about the domain and co-domain?

Answer 12

They are always subsets of objects in some data type

Question 13

What is Haskell?

Answer 13

A functional programming language

Question 14

What is a parameter in Haskell?

Answer 14

A reference declared in a function declaration

Question 15

What is an argument in Haskell?

Answer 15

A value or expression passed to a function

Question 16

What is function application?

Answer 16

The process of giving particular inputs to a function

Question 17

What are first-class objects?

Answer 17

An object that can:
- Appear in expressions
- Be assigned to a variable
- Be assigned as an argument
- Be returned in a function call

Question 18

What is unique about variables in functional programming?

Answer 18

The value of a variable is immutable and the program is stateless

Question 19

What is referential transparency?

Answer 19

A function that is called twice with the same parameters will always return the same result

Question 20

What is the advantage of referential transparency?

Answer 20

It is relatively easy to write correct, bug free programs

Question 21

What does it mean to have no side effects?

Answer 21

The only thing a function can do is calculate something and return a result so it has no side effects

Question 22

What is functional composition?

Answer 22

Combining 2 functions to get a new function, by using a function as an argument

Question 23

What are types?

Answer 23

Sets of values

Question 24

What are typeclasses?

Answer 24

Sets of types

Question 25

What is a type variable?

Answer 25

A variable that represents any type

Question 26

What is a higher order function?

Answer 26

A function that either takes a function as an argument or returns a function as a result

Question 27

How many arguments can a function in Haskell take?

Answer 27

Only 1, because each argument will result in a new function being created

Question 28

What is partial function application?

Answer 28

Fixing the values of some inputs to a function in order to produce another more specific function

Question 29

What is the map function?

Answer 29

A higher-order function that takes a list, treats each element as an input and applies the function to each element, returning a new list

Question 30

What is a list?

Answer 30

A collection of elements of the same type, enclosed in square brackets

Question 31

What is the max function?

Answer 31

A built-in library function that returns the maximum of 2 numbers

Question 32

What is the filter function?

Answer 32

A higher-order function that takes a predicate and a list, returning the elements within the list that satisfies the Boolean condition

Question 33

What is a predicate?

Answer 33

A boolean condition

Question 34

What is a fold function?

Answer 34

A higher-order function that reduces a lost to a single value via recursion

Question 35

What is the difference between foldl and foldr?

Answer 35

Foldl has the recursion starting at the leftmost value, Foldr has the recursion starting at the rightmost value

Question 36

What is the head of a list?

Answer 36

The first element in the list

Question 37

What is the tail of a list?

Answer 37

The last element in the list

Question 38

Can lists be modified?

Answer 38

No, they are immutable

Question 39

What does the function null do?

Answer 39

It tests for an empty list

Question 40

What is prepending?

Answer 40

Adding an element to the front of the list

Question 41

What is appending?

Answer 41

Adding an element to the end of a list