[abenedic]

> Listening to spoken English is not easy for non native speakers

Thank you for saying this. You clearly have a good understanding of English(far better than mine at least). I feel like this is an area that is glossed over. For every article that is written in english there are at least 10+ non-native speaker struggling to understand the work, who could extract something useful or help explicate the work.

[theoh]

In the case of this video, you aren't missing much. It's deliberately 'dense', according to the author, but the concept is simple.

Almost any app will involve some imperative code, but using pure functions within that, where possible, makes it easier to reason about what is going on. That's all there is to it. https://en.wikipedia.org/wiki/Referential_transparency