Functional Programming & Haskell - Computerphile

TL;DR

Functional programming is a programming style where functions have no side effects, leading to better code understanding, fewer bugs, and increased parallel computing capabilities.

Transcript

functional programming is essentially kind of programming where functions don't have side effects So what does it mean when you call a function you give it some inputs? And it will return some output and that's all that it does it doesn't modify the inputs It doesn't do something on the side people often talk about firing the missiles It can't do t... Read More

Key Insights

• 🥺 Functional programming focuses on writing functions without side effects, leading to code that is easier to understand and less prone to bugs.
• 🈸 Functional languages have found applications on the server side of internet applications, such as spam filtering, messaging apps, and social media platforms.
• 💯 The development of Haskell involved collaboration among different universities to create a shared core language, resulting in a widely used functional programming language.
• 👨‍💻 Functional programming languages handle memory management, and with the development of efficient compilers, code written in functional languages can achieve performance comparable to or better than conventional languages.
• 😄 Functional programming allows for parallel computing with ease, as functions have no side effects and can be evaluated independently.
• 💦 Privacy and security concerns are being addressed in the functional programming community, with work being done on languages and libraries that enforce privacy constraints.
• ⌛ QuickCheck, a testing tool for functional programming, generates tests automatically to check program behavior, saving time and effort for developers.

Questions & Answers

Q: What is functional programming and how does it differ from conventional programming?

Functional programming is a style where functions have no side effects, meaning they only take inputs and produce outputs without modifying the inputs. This is different from conventional programming, where functions can have additional effects besides returning their result, leading to potential bugs and difficulties in understanding the code.

Q: What are some examples of functional programming languages and their applications?

Haskell, which was partly designed by the speaker, is used for spam filtering on Facebook. Erlang, another functional programming language, was used to implement WhatsApp. Scala, a language inspired by Haskell, is used in Twitter's code. These examples show that functional languages are applied in various internet applications.

Q: How did the development of Haskell come about?

Initially, different universities were developing their own functional programming languages, but they couldn't share code due to different compilers. A proposal emerged to create a common core language, which eventually led to the development of Haskell. The name "Haskell" was chosen after Haskell Curry, a logician who worked with lambda calculus.

Q: Is functional programming slower than other programming languages?

Functional programming languages often provide memory management features, just like other modern programming languages. Although there may be a slight performance penalty due to the implementation details taken care of by functional languages, code written in functional languages can be as fast as, or even faster than, code written in conventional programming languages.

Summary & Key Takeaways

• Functional programming is based on functions that only have input and output, without modifying inputs or having side effects.

• By programming in a functional style, developers can have a deep understanding of the behavior of their functions and avoid common bugs.

• Functional programming languages like Haskell, Erlang, and Scala have been used in various internet applications such as spam filtering on Facebook, WhatsApp, and Twitter.