The document discusses major programming paradigms, focusing on imperative and declarative types, and outlines four key paradigms: procedural, object-oriented, logical, and functional programming. It emphasizes the differences between imperative (how to do something) and declarative (what to do) programming through various examples. Additionally, it highlights the advantages and disadvantages of each paradigm, providing insights into their applications and efficiency.

1. MAJOR PROGRAMMING
PARADIGMS
MUHAMMED ASIM YILDIZ

2. Inside
 What is Programming Paradigms?
 Imperative vs Declarative Programming Paradigms
 4 Major Programming Paradigms
 Procedural Programming Paradigm
 Logical Programming Paradigm
 Functional Programming Paradigm
 Object Oriented Programming Paradigm

3. Programming Paradigm
 Is an approach to programming a computer;
 Based on mathematical theory or
 A coherent set of principles

4. Imperative – Declarative Programming
Paradigms
 Question :
 I’m right next to Eagle Statue. How do I get to Digiturk from here?
 How can we define it with Imperative PP?
 How can we define it with Declarative PP?

5. Imperative Way
 Head east on Mumcu Bakkal Sokağı toward Şht. Asım Cd.
 Turn left onto Şht. Asım Cd.
 Continue onto Masuklar Ykş. (110m)
 Continue onto Yıldız Cd. (270m)
 Digiturk is on the right

6. Declarative Way
 Digiturk’s address is Cihannüma, Yıldız Cd., 34353 Beşiktaş/İstanbul

7. Imperative programming is like how you do something,
while declarative programming is more like what you do.

8. Another Example
 You go to a restaurant and approach the front desk
 If you say :
 I see that table located under the TV is empty
 I would like to sit there
 IMPERATIVE (define how to get a table)
 Or if you say :
 Table for one, please
 DECLARATIVE (what you want)

9. Many (if not all) declarative approaches
have some sort of underlying imperative abstraction.

10. Imperative-Declarative Relation
 The declarative response for restaurant assumes that the front-desk guy knows..
 Knowing the Digiturk address assumes you have a some sort of GPS that knows..
 ‘THE IMPERATIVE STEPS’

11. Examples of PP with
Programming Languages
 SQL :
 HTML :
<article>
<header>
<h1>Declarative Programming</h1>
<p>Sprinkle Declarative in your verbiage to sound smart</p>
</header>
</article>
SELECT * FROM Users WHERE Country=’Mexico’;

12. Examples of PP with
Programming Languages
 Javascript (write a function called double which takes an array, and return a new array where
the values doubled) :
function double (arr) {
let results = []
for (let i = 0; i < arr.length; i++){
results.push(arr[i] * 2)
}
return results
}
function double (arr) {
return arr.map((item) => item * 2)
}

13. Programming Languages by Paradigms
 Imperative: C, C++, Java
 Declarative: SQL, HTML
 (Can Be) Mix: JavaScript, C#, Python

14. 4 Major Programming Paradigms
 Imperative
 Procedural
 Object-Oriented
 Declarative
 Logical
 Functional

15. IMPERATIVE PROGRAMMING PARADIGMS

16. Procedural Programming Paradigm
 The entire program is a single algorithm consists of independent modules
 The complete functionality written linearly (step-by-step)

17. Procedural PP Example

18. Procedural PP Advantages
 Efficient (modules are easier to write)
 Close to the machine
 Best for expressing algorithms

19. Procedural PP Disadvantages
 The semantics of the program can be complex
 Hard to understand and hard to prove (lots of modules)
 Side effects make debugging harder
 Order is crucial (step-by-step)

20. Object Oriented Programming Paradigm
 Real-world objects are each viewed as seperate entities
 Each object has it’s own state which is modified only by built in methods
 Objects operated independently (communication is done by message passing)

21. OOP PP Example

22. OOP PP Advantages
 Inheritance (reusable code and code extensibility)
 Changing code without the need to change existing code (subclass)
 Encapsulation and information hiding
 Prevents data from being accessed by the code outside
 Define data as private and open them to outside by public methods
 Parallel code development with big teams
 More human-friendly and readable code

23. OOP PP Disadvantages
 First time coding can be more extensive (code duplication)
 Can create a massive amount of unnecessary code
 Can be slow because of the overhead (negligible)

24. DECLARATIVE PROGRAMMING PARADIGMS

25. Logical Programming Paradigm
 Execution of a logic program is a theorem proving process (Datalog, Prolog)
 Program statements express facts, rules and predicates
 It consists from a system of formal logic

26. Logical PP Example
 Given information about fatherhood and motherhood, determine grand parent relationship :
 Given the information called facts;
 John is father of Lily – father(john, lily)
 Kathy is mother of Lily – mother(kathy, lily)
 Lily is mother of Bill – mother(lily, bill)
 Ken is father of Karen – father(ken, karen)
 Who are grand parents of Bill?
 grandparent(X,Z) :- parent(X,Y), parent(Y,Z)
 parent(X,Y) :-father(X,Y)
 parent(X,Y) :-mother(X,Y).

27. Logical PP Advantages
 The system solves the problem
 Programming steps are kept to a minimum
 Proving the validity of the program is simple

28. Logical PP Disadvantages
 Not efficient as other programming paradigms
 Takes too much effort to create a program
 Not widely used (medical diagnosis, robot control etc.)

29. Functional Programming Paradigm
 Views all subprograms as functions (in mathematical sense)
 Functions take in arguments and return a single solution
 Solution returned is based entirely on the input
 The time which a function is called has no revelance

30. Functional PP Example

31. Functional PP Advantages
 High level of abstraction
 Functions suppress many of the programming details
 Removes the possibility of making too many errors (simple)
 Good candidates for programming to parallel computers

32. Functional PP Disadvantages
 Problems involving many variables or
 Problems with a lot of sequential code runs;
 Sometimes easier to implement with Object oriented programming

33. THANK YOU