Apa sebenarnya paradigma pengaturcaraan?

Pengaturcaraan
Mana-mana orang bodoh boleh menulis kod yang difahami oleh komputer. Pengaturcara yang baik menulis kod yang dapat difahami oleh manusia.

- Martin Fowler

Semasa memprogram, kerumitan selalu menjadi musuh. Program dengan kerumitan yang hebat, dengan banyak bahagian bergerak dan komponen yang saling bergantung, pada mulanya kelihatan mengagumkan. Namun, kemampuan untuk menerjemahkan masalah dunia nyata menjadi penyelesaian yang mudah atau elegan memerlukan pemahaman yang lebih mendalam.

Semasa mengembangkan aplikasi atau menyelesaikan masalah sederhana, kita sering mengatakan "Sekiranya saya mempunyai lebih banyak masa, saya akan menulis program yang lebih sederhana". Sebabnya, kami membuat program dengan kerumitan yang lebih besar. Semakin kurang kerumitan yang kita miliki, semakin mudah untuk men-debug dan memahami. Semakin kompleks program, semakin sukar untuk mengusahakannya.

Menguruskan kerumitan adalah perhatian utama pengaturcara . Jadi bagaimana pengaturcara menangani kerumitan? Terdapat banyak pendekatan umum yang mengurangkan kerumitan dalam program atau menjadikannya lebih terkawal. Salah satu pendekatan utama adalah paradigma pengaturcaraan. Mari selami paradigma pengaturcaraan!

Pengenalan paradigma pengaturcaraan

Istilah paradigma pengaturcaraan merujuk kepada gaya pengaturcaraan . Itu tidak merujuk pada bahasa tertentu, melainkan merujuk kepada cara anda memprogram.

Terdapat banyak bahasa pengaturcaraan yang terkenal tetapi semuanya perlu mengikuti beberapa strategi ketika mereka dilaksanakan. Dan strategi itu adalah paradigma.

Jenis paradigma pengaturcaraan

Paradigma pengaturcaraan Imperatif

Kata "imperatif" berasal dari bahasa Latin "impero" yang bermaksud "Saya memerintahkan".

Ini adalah perkataan yang sama dengan yang kita dapatkan dari "maharaja", dan itu cukup tepat. Anda maharaja. Anda memberi sedikit arahan kepada komputer untuk dilakukan dan ia melakukannya satu demi satu dan melaporkannya kembali.

Paradigma terdiri daripada beberapa pernyataan, dan setelah pelaksanaannya semua, hasilnya disimpan. Ini mengenai menulis senarai arahan untuk memberitahu komputer apa yang harus dilakukan langkah demi langkah.

Dalam paradigma pengaturcaraan yang mustahak, urutan langkah-langkahnya sangat penting, kerana langkah yang diberikan akan mempunyai akibat yang berbeza bergantung pada nilai pemboleh ubah semasa ketika langkah itu dijalankan.

Sebagai gambaran, mari kita cari jumlah sepuluh nombor semula jadi pertama dalam pendekatan paradigma penting.

Contoh dalam C:

#include  int main() { int sum = 0; sum += 1; sum += 2; sum += 3; sum += 4; sum += 5; sum += 6; sum += 7; sum += 8; sum += 9; sum += 10; printf("The sum is: %d\n", sum); //prints-> The sum is 55 return 0; }

Dalam contoh di atas, kami memerintahkan komputer apa yang harus dilakukan mengikut baris. Akhirnya, kami menyimpan nilai dan mencetaknya.

1.1 Paradigma pengaturcaraan prosedur

Pengaturcaraan prosedur (yang juga mustahak) membolehkan membagi arahan tersebut menjadi prosedur .

CATATAN: Prosedur bukan fungsi. Perbezaan antara keduanya adalah bahawa fungsi mengembalikan nilai, dan prosedur tidak. Lebih khusus lagi, fungsi dirancang untuk mempunyai kesan sampingan yang minimum, dan selalu menghasilkan output yang sama apabila diberi input yang sama. Prosedur, sebaliknya, tidak mempunyai nilai pulangan. Tujuan utama mereka adalah untuk menyelesaikan tugas yang diberikan dan menyebabkan kesan sampingan yang diinginkan.

Contoh prosedur yang baik adalah terkenal dengan gelung. Tujuan utama loop adalah untuk menyebabkan kesan sampingan dan tidak mengembalikan nilai.

Untuk menggambarkan, mari kita cari jumlah sepuluh nombor semula jadi dalam pendekatan paradigma prosedur.

Contoh dalam C: 

#include  int main() { int sum = 0; int i =0; for(i=1;i The sum is 55 return 0; }

Dalam contoh di atas, kami telah menggunakan simpul untuk gelung untuk mencari penjumlahan sepuluh nombor semula jadi yang pertama.

Bahasa yang menyokong paradigma pengaturcaraan prosedur adalah:

  • C
  • C ++
  • Jawa
  • ColdFusion
  • Pascal

Pengaturcaraan prosedur selalunya merupakan pilihan terbaik apabila:

  • Terdapat operasi yang kompleks yang merangkumi kebergantungan antara operasi, dan ketika ada kebutuhan untuk keterlihatan yang jelas dari berbagai keadaan aplikasi ('SQL loading', 'SQL loading', 'Network online', 'No audio hardware', dll). Ini biasanya sesuai untuk permulaan dan penutupan aplikasi (Holligan, 2016).
  • Program ini sangat unik dan beberapa elemen telah dikongsi (Holligan, 2016).
  • Program ini statik dan tidak dijangka akan berubah dari masa ke masa (Holligan, 2016).
  • Tidak ada atau hanya beberapa ciri yang diharapkan dapat ditambahkan ke dalam projek dari masa ke masa (Holligan, 2016).

Mengapa anda harus mempertimbangkan untuk mempelajari paradigma pengaturcaraan prosedur?

  • Ia mudah.
  • Kaedah yang lebih mudah untuk mengesan aliran program.
  • Ia mempunyai kemampuan untuk menjadi sangat modular atau berstruktur.
  • Memerlukan memori yang lebih sedikit: Ia cekap dan berkesan.

1.2 Paradigma pengaturcaraan berorientasikan objek

OOP adalah paradigma pengaturcaraan yang paling popular kerana kelebihannya yang unik seperti modulariti kod dan kemampuan untuk secara langsung mengaitkan masalah perniagaan dunia nyata dari segi kod.

Pengaturcaraan berorientasikan objek menawarkan kaedah berkelanjutan untuk menulis kod spaghetti. Ini membolehkan anda mendapatkan program sebagai rangkaian tambalan.

- Paul Graham

Ciri-ciri utama pengaturcaraan berorientasikan objek merangkumi Kelas, Abstraksi, Enkapsulasi, Warisan dan Polimorfisme.

A kelas adalah template atau pelan tindakan yang objek yang dicipta.

Objects are instances of classes. Objects have attributes/states and methods/behaviors. Attributes are data associated with the object while methods are actions/functions that the object can perform.

Abstraction separates the interface from implementation. Encapsulation is the process of hiding the internal implementation of an object.

Inheritance enables hierarchical relationships to be represented and refined. Polymorphism allows objects of different types to receive the same message and respond in different ways.

To illustrate, let's find the sum of first ten natural numbers in the object-oriented paradigm approach.

Example in Java:

public class Main { public static void main(String[] args) { Addition obj = new Addition(); obj.num = 10; int answer = obj.addValues(); System.out.println("The sum is = "+answer); //prints-> The sum is 55 } } class Addition { int sum =0; int num =0; int addValues(){ for(int i=1; i<=num;i++){ sum += i; } return sum; } }

We have a class Addition that has two states, sum and num which are initialized to zero. We also have a method addValues() which returns the sum of num numbers.

In the Main class, we've created an object, obj of Addition class. Then, we've initialized the num to 10 and we've called addValues() method to get the sum.

Languages that support the object-oriented paradigm:

  • Python
  • Ruby
  • Java
  • C++
  • Smalltalk

Object-oriented programming is best used when:

  • You have multiple programmers who don’t need to understand each component (Holligan, 2016).
  • There is a lot of code that could be shared and reused (Holligan, 2016).
  • The project is anticipated to change often and be added to over time (Holligan, 2016).

Why should you consider learning the object-oriented programming paradigm?

  • Reuse of code through Inheritance.
  • Flexibility through Polymorphism.
  • High security with the use of data hiding (Encapsulation) and Abstraction mechanisms.
  • Improved software development productivity: An object-oriented programmer can stitch new software objects to make completely new programs (The Saylor Foundation, n.d.).
  • Faster development: Reuse enables faster development (The Saylor Foundation, n.d.).
  • Lower cost of development: The reuse of software also lowers the cost of development. Typically, more effort is put into the object-oriented analysis and design (OOAD), which lowers the overall cost of development (The Saylor Foundation, n.d.).
  • Higher-quality software: Faster development of software and lower cost of development allows more time and resources to be used in the verification of the software. Object-oriented programming tends to result in higher-quality software (The Saylor Foundation, n.d.).

1.3 Parallel processing approach

Parallel processing is the processing of program instructions by dividing them among multiple processors.

A parallel processing system allows many processors to run a program in less time by dividing them up.

Languages that support the Parallel processing approach:

  • NESL (one of the oldest ones)
  • C
  • C++

Parallel processing approach is often the best use when:

  • You have a system that has more than one CPU or multi-core processors which are commonly found on computers today.
  • You need to solve some computational problems that take hours/days to solve even with the benefit of a more powerful microprocessor.
  • You work with real-world data that needs more dynamic simulation and modeling.

Why should you consider learning the parallel processing approach?

  • Speeds up performance.
  • Often used in Artificial Intelligence. Learn more here: Artificial Intelligence and Parallel Processing by Seyed H. Roosta.
  • It makes it easy to solve problems since this approach seems to be like a divide and conquer method.

Here are some useful resources to learn more about parallel processing:

  1. Parallel Programming in C by Paul Gribble
  2. Introduction to Parallel Programming with MPI and OpenMP by Charles Augustine
  3. INTRODUCTION TO PARALLEL PROGRAMMING WITH MPI AND OPENMP by Benedikt Steinbusch

2. Declarative programming paradigm

Declarative programming is a style of building programs that expresses the logic of a computation without talking about its control flow.

Declarative programming is a programming paradigm in which the programmer defines what needs to be accomplished by the program without defining how it needs to be implemented. In other words, the approach focuses on what needs to be achieved instead of instructing how to achieve it.

Imagine the president during the state of the union declaring their intentions for what they want to happen. On the other hand, imperative programming would be like a manager of a McDonald's franchise. They are very imperative and as a result, this makes everything important. They, therefore, tell everyone how to do everything down to the simplest of actions.

So the main differences are that imperative tells you how to do something and declarative tells you what to do.

2.1 Logic programming paradigm

The logic programming paradigm takes a declarative approach to problem-solving. It's based on formal logic.

The logic programming paradigm isn't made up of instructions - rather it's made up of facts and clauses. It uses everything it knows and tries to come up with the world where all of those facts and clauses are true.

For instance, Socrates is a man, all men are mortal, and therefore Socrates is mortal.

The following is a simple Prolog program which explains the above instance:

 man(Socrates). mortal(X) :- man(X).

The first line can be read, "Socrates is a man.'' It is a base clause, which represents a simple fact.

The second line can be read, "X is mortal if X is a man;'' in other words, "All men are mortal.'' This is a clause, or rule, for determining when its input X is "mortal.'' (The symbol ":-'', sometimes called a turnstile, is pronounced "if''.) We can test the program by asking the question:

 ?- mortal(Socrates).

that is, "Is Socrates mortal?'' (The "?-'' is the computer's prompt for a question). Prolog will respond "yes''. Another question we may ask is: 

?- mortal(X).

That is, "Who (X) is mortal?'' Prolog will respond "X = Socrates''.

To give you an idea, John is Bill's and Lisa's father. Mary is Bill's and Lisa's mother. Now, if someone asks a question like "who is the father of Bill and Lisa?" or "who is the mother of Bill and Lisa?" we can teach the computer to answer these questions using logic programming.

Example in Prolog:

/*We're defining family tree facts*/ father(John, Bill). father(John, Lisa). mother(Mary, Bill). mother(Mary, Lisa). /*We'll ask questions to Prolog*/ ?- mother(X, Bill). X = Mary

Example explained:

father(John, Bill).

The above code defines that John is Bill's father.

We're asking Prolog what value of X makes this statement true? X should be Mary to make the statement true. It'll respond X = Mary

?- mother(X, Bill). X = Mary

Languages that support the logic programming paradigm:

  • Prolog
  • Absys
  • ALF (algebraic logic functional programming language)
  • Alice
  • Ciao

Logic programming paradigm is often the best use when:

  • If you're planning to work on projects like theorem proving, expert systems, term rewriting, type systems and automated planning.

Why should you consider learning the logic programming paradigm?

  • Easy to implement the code.
  • Debugging is easy.
  • Since it's structured using true/false statements, we can develop the programs quickly using logic programming.
  • As it's based on thinking, expression and implementation, it can be applied in non-computational programs too.
  • It supports special forms of knowledge such as meta-level or higher-order knowledge as it can be altered.

2.2 Functional programming paradigm

The functional programming paradigm has been in the limelight for a while now because of JavaScript, a functional programming language that has gained more popularity recently.

The functional programming paradigm has its roots in mathematics and it is language independent. The key principle of this paradigm is the execution of a series of mathematical functions.

You compose your program of short functions. All code is within a function. All variables are scoped to the function.

In the functional programming paradigm, the functions do not modify any values outside the scope of that function and the functions themselves are not affected by any values outside their scope.

To illustrate, let's identify whether the given number is prime or not in the functional programming paradigm.

Example in JavaScript:

function isPrime(number){ for(let i=2; i<=Math.floor(Math.sqrt(number)); i++){ if(number % i == 0 ){ return false; } } return true; } isPrime(15); //returns false

In the above example, we've used Math.floor() and Math.sqrt() mathematical functions to solve our problem efficiently. We can solve this problem without using built-in JavaScript mathematical functions, but to run the code efficiently it is recommended to use built-in JS functions.

number is scoped to the function isPrime() and it will not be affected by any values outside its scope. isPrime() function always produces the same output when given the same input.

NOTE: there are no for and while loops in functional programming. Instead, functional programming languages rely on recursion for iteration (Bhadwal, 2019).

Languages that support functional programming paradigm:

  • Haskell
  • OCaml
  • Scala
  • Clojure
  • Racket
  • JavaScript

Functional programming paradigm is often best used when:

  • Working with mathematical computations.
  • Working with applications aimed at concurrency or parallelism.

Why should you consider learning the functional programming paradigm?

  • Functions can be coded quickly and easily.
  • General-purpose functions can be reusable which leads to rapid software development.
  • Unit testing is easier.
  • Debugging is easier.
  • Overall application is less complex since functions are pretty straightforward.

2.3 Database processing approach

This programming methodology is based on data and its movement. Program statements are defined by data rather than hard-coding a series of steps.

A database is an organized collection of structured information, or data, typically stored electronically in a computer system. A database is usually controlled by a database management system (DBMS) ("What is a Database", Oracle, 2019).

To process the data and querying them, databases use tables. Data can then be easily accessed, managed, modified, updated, controlled and organized.

A good database processing approach is crucial to any company or organization. This is because the database stores all the pertinent details about the company such as employee records, transaction records and salary details.

Most databases use Structured Query Language (SQL) for writing and querying data.

Here’s an example in database processing approach (SQL):

CREATE DATABASE personalDetails; CREATE TABLE Persons ( PersonID int, LastName varchar(255), FirstName varchar(255), Address varchar(255), City varchar(255) );

The PersonID column is of type int and will hold an integer. The LastName, FirstName, Address, and City columns are of type varchar and will hold characters, and the maximum length for these fields is 255 characters.

The empty Persons table will now look like this:

Database processing approach is often best used when:

  • Working with databases to structure them.
  • Accessing, modifying, updating data on the database.
  • Communicating with servers.

Why are databases important and why should you consider learning database processing approach?

  • Massive amount of data is handled by the database: Unlike spreadsheet or other tools, databases are used to store large amount of data daily.
  • Accurate: With the help of built-in functionalities in a database, we can easily validate.
  • Easy to update data: Data Manipulation Languages (DML) such as SQL are used to update data in a database easily.
  • Data integrity: With the help of built-in validity checks, we can ensure the consistency of data.

Conclusion

Programming paradigms reduce the complexity of programs. Every programmer must follow a paradigm approach when implementing their code. Each one has its advantages and disadvantages.

If you're a beginner, I would like to suggest learning object-oriented programming and functional programming first. Understand their concepts and try to apply them in your projects.

For example, if you're learning object-oriented programming, the pillars of object-oriented programming are Encapsulation, Abstraction, Inheritance and Polymorphism. Learn them by doing it. It will help you to understand their concepts on a deeper level, and your code will be less complex and more efficient and effective.

I strongly encourage you to read more related articles on programming paradigms. I hope this article helped you.

Please feel free to let me know if you have any questions.

You can contact and connect with me on Twitter @ThanoshanMV.

Thank you for reading.

Happy Coding!

References

  • Akhil Bhadwal. (2019). Functional Programming: Concepts, Advantages, Disadvantages, and Applications
  • Alena Holligan. (2016). When to use OOP over procedural coding
  • The Saylor Foundation. (n.d.). Advantages and Disadvantages of Object-Oriented Programming (OOP)
  • What is a Database | Oracle. (2019).