Point-Free Videos
248 episodes - English - Latest episode: about 20 hours ago - ★★★★★ - 2 ratingsPoint-Free is a video series that explores advanced topics in the Swift programming language. Each episode covers a topic that may seem complex and academic at first, but turns out to be quite simple. At the end of each episode we’ll ask “what’s the point?!”, so that we can bring the concepts back down to earth and show how these ideas can improve the quality of your code today.
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Episodes
The Many Faces of Flat-Map: Part 2
January 16, 2019 07:00 - 27 minutes - 43.2 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Now that we know that `flatMap` is important for flattening nested arrays and optionals, we should feel empowered to define it on our own types. This leads us to understanding its structure more in depth and how it's different from `map` and `zip`.
The Many Faces of Flat‑Map: Part 1
January 07, 2019 07:00 - 25 minutes - 92.1 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Previously we've discussed the `map` and `zip` operations in detail, and today we start completing the trilogy by exploring `flatMap`. This operation is precisely the tool needed to solve a nesting problem that `map` and `zip` alone cannot.
The Many Faces of Flat-Map: Part 1
January 07, 2019 07:00 - 25 minutes - 92.1 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Previously we've discussed the `map` and `zip` operations in detail, and today we start completing the trilogy by exploring `flatMap`. This operation is precisely the tool needed to solve a nesting problem that `map` and `zip` alone cannot.
🆓 A Tour of Snapshot Testing
December 18, 2018 07:00 - 29 minutes - 430 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- Our snapshot testing library is now officially open source! In order to show just how easy it is to integrate the library into any existing code base, we add some snapshot tests to a popular open source library for attributed strings. This gives us the chance to see ...
Async Functional Refactoring
December 17, 2018 07:00 - 34 minutes - 68.5 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- The snapshot testing library we have been designing over the past few weeks has a serious problem: it can't snapshot asynchronous values, like web views and anything that uses delegates or callbacks. Today we embark on a no-regret refactor to fix this problem with the help of a well-studied and well-u...
Witness-Oriented Library Design
November 26, 2018 05:00 - 39 minutes - 97.4 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We previously refactored a library using protocols to make it more flexible and extensible but found that it wasn't quite as flexible or extensible as we wanted it to be. This week we re-refactor our protocols away to concrete datatypes using our learnings from earlier in the series.
Protocol-Oriented Library Design: Part 2
November 19, 2018 06:00 - 22 minutes - 104 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- With our library fully generalized using protocols, we show off the flexibility of our abstraction by adding new conformances and functionality. In fleshing out our library we find out why protocols may not be the right tool for the job.
Protocol-Oriented Library Design: Part 1
November 12, 2018 09:00 - 22 minutes - 129 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Perhaps the most popular approach to code reuse and extensibility in Swift is to liberally adopt protocol-oriented programming, and many Swift libraries are designed with protocol-heavy APIs. In today's episode we refactor a sample library to use protocols and examine the pros and cons of this approach.
Advanced Protocol Witnesses: Part 2
November 05, 2018 09:00 - 37 minutes - 85.3 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We complete our dictionary for translating Swift protocol concepts into concrete datatypes and functions. This includes protocol inheritance, protocol extensions, default implementations _and_ protocols with associated types. Along the way we will also show how concrete types can express things that a...
Advanced Protocol Witnesses: Part 1
October 29, 2018 09:00 - 35 minutes - 49.8 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Now that we know it's possible to replace protocols with concrete datatypes, and now that we've seen how that opens up new ways to compose things that were previously hidden from us, let's go a little deeper. We will show how to improve the ergonomics of writing Swift in this way, and show what Swift'...
Protocol Witnesses: Part 2
October 22, 2018 05:48 - 22 minutes - 47.5 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Last time we covered some basics with protocols, and demonstrated one of their biggest pitfalls: types can only conform to a protocol a single time. Sometimes it's valid and correct for a type to conform to a protocol in many ways. We show how to remedy this by demonstrating that one can scrap any pro...
Protocol Witnesses: Part 1
October 15, 2018 05:48 - 18 minutes - 55.9 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Protocols are a great tool for abstraction, but aren't the only one. This week we begin to explore the tradeoffs of using protocols by highlighting a few areas in which they fall short in order to demonstrate how we can recover from these problems using a different tool and different tradeoffs.
Decodable Randomness: Part 2
October 01, 2018 05:57 - 26 minutes - 37.6 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- This week we compare our `Decodable` solution to building random structures with a composable solution involving the `Gen` type, exploring the differences and trade-offs of each approach. Along the way we'll rediscover a familiar old friend with a brand new application.
Decodable Randomness: Part 1
September 24, 2018 05:57 - 21 minutes - 65.9 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- This week we dive deeper into randomness and composition by looking to a seemingly random place: the `Decodable` protocol. While we're used to using the `Codable` set of protocols when working with JSON serialization and deserialization, it opens the opportunity for so much more.
Composable Randomness
September 17, 2018 05:57 - 40 minutes - 27.8 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Randomness is a topic that may not seem so functional, but it gives us a wonderful opportunity to explore composition. After a survey of what randomness looks like in Swift today, we'll build a complex set of random APIs from just a single unit.
🆓 DSLs vs. Templating Languages
September 10, 2018 05:57 - 33 minutes - 454 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- Templating languages are the most common way to render HTML in web frameworks, but we don't think they are the best way. We compare templating languages to the DSL we previously built, and show that the DSL fixes many problems that templates have, while also revealin...
An HTML DSL
September 03, 2018 05:57 - 23 minutes - 39.9 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- This week we apply domain-specific languages to a very real-world problem: representing and rendering HTML. We code up a simple but powerful solution that forms the foundation of what we use to build the Point-Free website.
Domain‑Specific Languages: Part 2
August 27, 2018 05:57 - 20 minutes - 70.8 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We finish our introduction to DSLs by adding two new features to our toy example: support for multiple variables and support for let-bindings so that we can share subexpressions within a larger expression. With these fundamentals out of the way, we will be ready to tackle a real-world DSL soon!
Domain Specific Languages: Part 2
August 27, 2018 05:57 - 20 minutes - 70.8 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We finish our introduction to DSLs by adding two new features to our toy example: support for multiple variables and support for let-bindings so that we can share subexpressions within a larger expression. With these fundamentals out of the way, we will be ready to tackle a real-world DSL soon!
Domain Specific Languages: Part 1
August 20, 2018 05:57 - 24 minutes - 25.9 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We interact with domain specific languages on a daily basis, but what does it take to build your own? After introducing the topic, we will begin building a toy example directly in Swift, which will set the foundation for a future DSL with far-reaching applications.
Domain‑Specific Languages: Part 1
August 20, 2018 05:57 - 24 minutes - 25.9 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We interact with domain-specific languages on a daily basis, but what does it take to build your own? After introducing the topic, we will begin building a toy example directly in Swift, which will set the foundation for a future DSL with far-reaching applications.
🆓 The Many Faces of Zip: Part 3
August 06, 2018 05:57 - 24 minutes - 478 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- The third, and final, part of our introductory series to `zip` finally answers the question: "What's the point?"
The Many Faces of Zip: Part 2
July 30, 2018 05:57 - 36 minutes - 63.3 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- In part two of our series on `zip` we will show that many types support a `zip`-like operation, and some even support multiple distinct implementations. However, not all `zip`s are created equal, and understanding this can lead to some illuminating properties of our types.
The Many Faces of Zip: Part 1
July 23, 2018 09:57 - 28 minutes - 39.4 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- The `zip` function comes with the Swift standard library, but its utility goes far beyond what we can see there. Turns out, `zip` generalizes a function that we are all familiar with, and it can unify many seemingly disparate concepts. Today we begin a multipart journey into exploring the power behind...
🆓 A Tour of Point-Free
July 16, 2018 09:57 - 39 minutes - 310 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- Join us for a tour of the code base that powers this very site and see what functional programming can look like in a production code base! We'll walk through cloning the repo and getting the site running on your local machine before showing off some of the fun funct...
Playground Driven Development
July 09, 2018 09:57 - 24 minutes - 34.3 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We use Swift playgrounds on this series as a tool to dive deep into functional programming concepts, but they can be so much more. Today we demonstrate a few tricks to allow you to use playgrounds for everyday development, allowing for a faster iteration cycle.
NonEmpty
June 25, 2018 09:57 - 49 minutes - 42 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We often deal with collections that we know can never be empty, yet we use arrays to model them. Using the ideas from our last episode on algebraic data types, we develop a `NonEmpty` type that can be used to transform any collection into a non-empty version of itself.
Contravariance
June 12, 2018 09:57 - 38 minutes - 51.9 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Let's explore a type of composition that defies our intuitions. It appears to go in the opposite direction than we are used to. We'll show that this composition is completely natural, hiding right in plain sight, and in fact related to the Liskov Substitution Principle.
Algebraic Data Types: Generics and Recursion
June 11, 2018 09:57 - 47 minutes - 53.4 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Our third installment of algebraic data types explores how generics and recursive data types manifest themselves in algebra. This exploration allows us to construct a useful, precise type that can be useful in everyday programming.
Dependency Injection Made Comfortable
June 04, 2018 09:57 - 28 minutes - 67.2 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Let's have some fun with the "environment" form of dependency injection we previously explored. We're going to extract out a few more dependencies, strengthen our mocks, and use our Overture library to make manipulating the environment friendlier.
Styling with Overture
May 28, 2018 09:57 - 29 minutes - 44.5 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We revisit an old topic: styling UIKit components. Using some of the machinery we have built from previous episodes, in particular setters and function composition, we refactor a screen's styles to be more modular and composable.
Dependency Injection Made Easy
May 21, 2018 09:57 - 35 minutes - 28.9 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Today we're going to control the world! Well, dependencies to the outside world, at least. We'll define the "dependency injection" problem and show a lightweight solution that can be implemented in your code base with little work and no third party library.
Setters: Ergonomics & Performance
May 14, 2018 09:57 - 34 minutes - 25.7 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Functional setters can be very powerful, but the way we have defined them so far is not super ergonomic or performant. We will provide a friendlier API to use setters and take advantage of Swift's value mutation semantics to make setters a viable tool to bring into your code base _today_.
The Many Faces of Map
April 23, 2018 09:57 - 31 minutes - 55.1 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Why does the `map` function appear in every programming language supporting "functional" concepts? And why does Swift have _two_ `map` functions? We will answer these questions and show that `map` has many universal properties, and is in some sense unique.
Tagged
April 16, 2018 09:57 - 26 minutes - 32.4 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We typically model our data with very general types, like strings and ints, but the values themselves are often far more specific, like emails and ids. We'll explore how this can lead to subtle runtime bugs and how we can strengthen these types in an ergonomic way using several features new to Swift 4.1.
Composition without Operators
April 09, 2018 09:57 - 21 minutes - 20.5 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- While we unabashedly promote custom operators in this series, we understand that not every codebase can adopt them. Composition is too important to miss out on due to operators, so we want to explore some alternatives to unlock these benefits.
🆓 A Tale of Two Flat‑Maps
March 27, 2018 09:57 - 25 minutes - 157 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- Swift 4.1 deprecated and renamed a particular overload of `flatMap`. What made this `flatMap` different from the others? We'll explore this and how understanding that difference helps us explore generalizations of the operation to other structures and derive new, use...
🆓 A Tale of Two Flat-Maps
March 27, 2018 09:57 - 25 minutes - 157 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- Swift 4.1 deprecated and renamed a particular overload of `flatMap`. What made this `flatMap` different from the others? We'll explore this and how understanding that difference helps us explore generalizations of the operation to other structures and derive new, use...
Algebraic Data Types: Exponents
March 26, 2018 09:57 - 38 minutes - 29.6 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- We continue our explorations into algebra and the Swift type system. We show that exponents correspond to functions in Swift, and that by using the properties of exponents we can better understand what makes some functions more complex than others.
Getters and Key Paths
March 19, 2018 09:57 - 28 minutes - 13.8 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Key paths aren’t just for setting. They also assist in getting values inside nested structures in a composable way. This can be powerful, allowing us to make the Swift standard library more expressive with no boilerplate.
Setters and Key Paths
March 12, 2018 09:57 - 31 minutes - 34 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- This week we explore how functional setters can be used with the types we build and use everyday. It turns out that Swift generates a whole set of functional setters for you to use, but it can be hard to see just how powerful they are without a little help.
Functional Setters
March 05, 2018 10:57 - 20 minutes - 11.8 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- The programs we write can be reduced to transforming data from one form into another. We’re used to transforming this data imperatively, with setters. There’s a strange world of composition hiding here in plain sight, and it has a surprising link to a familiar functional friend.
Higher-Order Functions
February 26, 2018 13:57 - 22 minutes - 35.5 MB VideoSubscriber-Only: Today's episode is available only to subscribers. If you are a Point-Free subscriber you can access your private podcast feed by visiting https://www.pointfree.co/account. --- Most of the time we interact with code we did not write, and it doesn’t always play nicely with the types of compositions we have developed in previous episodes. We explore how higher-order functions can help unlock even more composability in our everyday code.
🆓 Algebraic Data Types
February 19, 2018 13:12 - 36 minutes - 186 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- What does the Swift type system have to do with algebra? A lot! We’ll begin to explore this correspondence and see how it can help us create type-safe data structures that can catch runtime errors at compile time.
🆓 UIKit Styling with Functions
February 12, 2018 13:12 - 27 minutes - 310 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- We bring tools from previous episodes down to earth and apply them to an everyday task: UIKit styling. Plain functions unlock worlds of composability and reusability in styling of UI components. Have we finally solved the styling problem?
🆓 Side Effects
February 05, 2018 06:11 - 44 minutes - 227 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- Side effects: can’t live with ’em; can’t write a program without ’em. Let’s explore a few kinds of side effects we encounter every day, why they make code difficult to reason about and test, and how we can control them without losing composition.
🆓 Functions
January 29, 2018 06:11 - 20 minutes - 189 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- Our first episode is all about functions! We talk a bit about what makes functions special, contrasting them with the way we usually write code, and have some exploratory discussions about operators and composition.
🆓 We launched!
January 29, 2018 06:11 - 2 minutes - 86.3 MB VideoEvery once in awhile we release a new episode free for all to see, and today is that day! Please enjoy this episode, and if you find this interesting you may want to consider a subscription https://www.pointfree.co/pricing. --- Point-Free is here, bringing you videos covering functional programming concepts using the Swift language. Take a moment to hear from the hosts about what to expect from this new series.