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Kotlin Functional Programming - Introduction

This is a lecture for beginners in Kotlin functional programming. After learning the syntax related to functional programming, you will learn what side effects, pure functions, and referential transparency are, and how to pass functions back and forth and use them in practice.

(5.0) 5 reviews

96 learners

  • seyol
함수형
Functional Programming
Kotlin
functional
oop

Reviews from Early Learners

What you will learn!

  • Kotlin Functional Programming Syntax

  • Basic theory of functional programming (side effects, pure functions, etc.)

  • Practical techniques for functional programming that can be used in practice

  • How to use object-oriented and functional programming together

🔥 Early bird special + special price in progress!

Functional programming starting from 38,500 won -> 28,875 won (30% discount with Inflearn open coupon)

🚨 Hurry up!

  • Automatically ends when 300 students are reached


  • Future updates are also provided free of charge

  • After the early bird ends, the price will increase to 49,500 won.

Now is the cheapest opportunity! 🎯

The world of functional programming starting with pure functions! 🚀

Functional programming, essential in practice, now learn it with Kotlin!

Are you having these concerns? 🤔

  • Functional programming, I don't know where to start

  • I want to learn functional programming that I can use immediately in my work.

  • Monads are still difficult! I want to learn them step by step from the basics.

  • I want to make my code more secure and maintainable.

Preview the lecture 👀

Learn the core of functional programming, “Side Effects and Pure Functions”!

// Before: Code with side effects fun orderCoffee (paymentCard: PaymentCard ) : Coffee { val coffee = Coffee() paymentCard.charge(coffee.price) // Side effect: Card payment return coffee } // After: Pure function with side effects removed fun orderCoffee (paymentCard: PaymentCard ) : Order { val coffee = Coffee() val transaction = Transaction(paymentCard, coffee.price) return Order(coffee, transaction) }

💡 Two codes that look similar at first glance,
But one is dangerous and one is safe.
If you're curious about the difference, check out the lecture!

A world of pure code led by the functional paradigm 🌟

To avoid getting lost in complex business logic,
We need a compass called pure functions.

Minimize state changes,
Pure functions maximize,
Safe with referential transparency.

Create better code with the functional programming paradigm.

In this lesson, you will learn! 📚

Section 0⃣ Lecture Introduction

Learn what functional programming is and why you need it!

  • What is the difference between object-oriented and functional?

  • What are the benefits of functional programming in practice?

Section 1⃣ Kotlin Functional Programming Grammar

Learn the basics of functional programming with Kotlin!

  • The functional world starting with lambda expressions 🎯

  • Writing more flexible code with generics

  • The charm of higher-order functions that exchange functions

Section 2⃣ Functional Programming Fundamentals

Let's take a look at the core concepts of functional programming one by one!

  • Why should side effects be avoided? 🚫

  • Creating predictable code with referential transparency 🎯

  • Writing safe code with pure functions

  • Creating flexible functions with currying 🔄

  • In addition to explanations of each concept, a workbook and detailed explanations are provided to help you improve your understanding. You can practice what you have learned right away, making it easier to understand. 🖊

Section 3⃣ Functional Programming in Practice

Learn functional techniques that you can apply to real-world projects!

  • Practical Functional Programming with Payment Systems 💳

  • Creating bug-free code with immutability 🛡

  • Increasing reusability with higher-order functions

📚 Provides abundant learning materials

  • Detailed lecture notes : 18 PDFs (approximately 50 pages), including diagrams and code for key sections

  • Lecture Slides : 42 pages of PPT, visualizing key content

  • All materials are downloadable : learn anywhere, anytime!

I recommend this to these people! 👍

Anyone who knows basic Kotlin grammar
Those who want to apply functional programming in practice
Anyone who wants to write better code

I don't recommend this to these people! 🚫

For those who don't know basic Kotlin grammar
Those who are already proficient in functional programming

Frequently Asked Questions

Q. Is basic knowledge of Kotlin required?

A. Yes, I recommend it to those who know the basic grammar of Kotlin.

Q. Can this be applied directly in practice?

A. Yes! You can experience the actual situations you encounter in the field step by step:

1⃣ Start simple

  • Implementing a basic payment system


2⃣ Add realistic requirements

  • Add a new payment method

  • Applying complex discount policies

  • Code becomes increasingly complex after reflecting real-time policy change requirements

3⃣ Improve functionally

  • Remove side effects

  • Ensuring immutability

  • Improved referential transparency

  • Improve reusability with higher-order functions

💡 Since you will learn with examples similar to real-world environments, you can apply what you learn to your work right away!

Lecture Materials 🛠

  • IntelliJ IDEA (also available with Community Edition)

  • Understanding Kotlin's basic grammar

  • Passion to learn functional programming

Pre-Class Checklist

  • Do you understand the basic syntax of Kotlin?

  • Want to learn the basics of functional programming?

  • Want to learn with practical, applicable examples?

If you checked everything, let's get started! 🎯

🎁 Master Kotlin with Functionality!

If you leave a review after taking more than 50% of the course,
" [Kotlin Grammar to Practice (Java to Kotlin Practice)] " Lecture
We'll give you a 50% discount coupon !

From basics to practice, an introductory course on Kotlin for Java developers
Come see us at a special discount price! 🚀

How to participate

  1. Attend more than 50% of this course

  2. After writing the course review, submit the registration form .

  3. Issuing discount coupons (takes 1-2 days)

From basic grammar to practical Kotlin-like coding methods,
Complete your path to becoming a Kotlin master with functional programming!

Recommended for
these people

Who is this course right for?

  • Those who are familiar with Kotlin grammar

  • People who are struggling to improve complex code

  • If you are interested in functional programming

Need to know before starting?

  • Understanding the Basics of Kotlin Grammar

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Learn, Share & Communicate 15년차 개발자 양세열입니다.

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  • (교육활동) 패스트캠퍼스, 제로베이스 부트캠프 온라인 강의 및 온오프 강연 진행

Curriculum

All

31 lectures ∙ (5hr 51min)

Course Materials:

Lecture resources
Published: 
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Reviews

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5 reviews

5.0

5 reviews

  • country님의 프로필 이미지
    country

    Reviews 8

    Average Rating 5.0

    5

    100% enrolled

    I used Kotlin like Java, but I appreciate that you explained Kotlin & Functional Programming in an easy-to-understand way. I'm looking forward to the intermediate level too~

    • seyol
      Instructor

      Country, thank you so much for your valuable feedback! 😃 I'm currently using functional programming in my work, in ways that are more diverse and complex, but also concise (?). I'm thinking about how to convey this in a way that's easy to understand and can be applied in various situations. ^^ Once I've figured out how to deliver it well, I'll definitely return with an intermediate functional programming course. I'm rooting for you to build a successful career with even more amazing and maintainable code!

  • crzhacko5665님의 프로필 이미지
    crzhacko5665

    Reviews 1

    Average Rating 5.0

    5

    35% enrolled

    This course is well designed to help Kotlin beginners learn the concepts of functional programming and how to apply them in practice. It provides a friendly explanation of basic grammar such as functions, lambdas, and generic types, and provides examples to help you easily understand important concepts of functional programming such as side effects and referential transparency. In particular, the part that shows how to apply what you have learned through practical cases was very useful. I recommend it to Kotlin beginners who want to lay the foundation for functional programming!

    • seyol
      Instructor

      Thank you, Tommy, for your detailed review! 🙏 I put a lot of thought into making the course easy for beginners to understand and apply to their work, and I'm so glad that my intentions came through. 😊 I'm especially glad to hear that the practical case section was helpful. ^^ I'll continue to provide better lectures in the future! Thank you again for your valuable feedback. ✨

  • sunsuking5399님의 프로필 이미지
    sunsuking5399

    Reviews 6

    Average Rating 5.0

    5

    74% enrolled

    I took this course because I wanted to learn Kotlin properly after just using it without formally learning it. It seems really good!

    • seyol
      Instructor

      Thank you for your valuable review, Min Jun-soo! Kotlin supports functional programming more naturally. You can write more readable and manageable code by using its simple grammar, support for immutability, and easier use of higher-order functions. I think you will enjoy writing test code more if you apply parts like kotest used in the sample code of the lecture to your work. If you have any other questions, please feel free to ask me anytime! 🚀 Thank you so much for your valuable review. 😆

  • cglee0790143님의 프로필 이미지
    cglee0790143

    Reviews 1

    Average Rating 5.0

    5

    52% enrolled

    I'm converting my code from Java to Kotlin and I've received a lot of help! I've gained confidence that I can use Kotlin properly by not just using Kotlin syntax but also improving it by using Kotlin's functional techniques!

    • seyol
      Instructor

      Thank you for your first review, cglee079! 🙏 I was nervous waiting for your review, but I'm so glad that my intentions were conveyed well! Kotlin not only allows you to handle Java code safely, but it also supports functional programming wonderfully, allowing you to create more powerful and secure code. Switching from Java to Kotlin is a big challenge in itself, but I'm really proud that you gained confidence by applying functional programming to it! 😄 I think you're having an experience where your code is becoming safer and cleaner by utilizing the advantages of functional programming. You'll become even more addicted to the charm of functional programming in the future! ✨ If you have any difficulties applying functional programming, please feel free to ask me any time. I will do my best to help you to the best of my knowledge. I will continue to visit you with good content that you can apply directly to your work. Have a happy Christmas and a happy New Year! 🎄

  • dbrjdn20513546님의 프로필 이미지
    dbrjdn20513546

    Reviews 38

    Average Rating 5.0

    Edited

    5

    32% enrolled

    It's great for casual listening!

    $29.70

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