Wrocław TypeScript Online #15

👨🏻🇫🇷Nicolas DUBIEN: Property-based testing: from zero to hero

Property based testing has been introduced by QuickCheck in Haskell years ago. It is a pretty well known technic to test apps in the functional world. Nonetheless, it is still pretty unknown outside of the functional world.

This talk will introduce the benefits that property based testing can have to increase the confidence you have in your tests. This new tool will make you able to detect unexpected bugs earlier and easily in various kinds of problems: from algorithms to ui interfaces.

Examples shown during the talk will be written using fast-check, a property based testing framework written in TypeScript that already discovered bugs in some huge libraries of the JavaScript ecosystem (eg.: Jest, Jasmine). But everything can be easily adapted to other frameworks in other languages.

About Nicolas:

Frontend software engineer for a start-up called Pigment launched in September 2019 and based in Paris. I am mostly working in TypeScript to build a React app - and sometimes a bit of C#.

Before that I have been working in C++ for 3yrs, then C# and TypeScript to build an Angular app for 2yrs.

Outside of the work, I am the author and maintainer of fast-check. I did multiple talks about it and proved it useful to detect bugs in many huge libraries so I really believe it can help the whole community.

GitHub: @dubzzz
Twitter: @ndubien

👨🏻🇺🇸Robbie Ostrow: Taking Types Too Far: Checking the Collatz Conjecture at Compile Time

This talk is based on a blog post I wrote back in December: https://ostro.ws/2019/12/09/taking-types-too-far/

This talk will build up Peano Arithmetic from scratch within the Typescript type system, where we use our newfound power to check the Collatz conjecture (well, at least for really short chains.) No prior number theory experience is required. Runtime side-effects are strictly forbidden.

If there's interest, I may also discuss using the same ideas while writing https://github.com/ostrowr/ts-json-validator

Now that I'm under quarantine, I figured it would be nice to give a remote talk!

About Robbie:

I'm a software engineer sheltering-in-place in San Francisco. I work for a startup called Vanta and occasionally like to abuse tools to solve tasks that they have no business solving.

Website: https://ostro.ws
GitHub: @ostrowr