A Gentle, Practical Introduction to Path-Dependent Types

Consider an HTTP API that responds with different fields based on the type of the input provided. How might you build a type-safe client to interact with this API? Is your code littered with Options? Do you resort to casting?

During this talk, we’ll work through a cleaner, safer solution using Scala’s path-dependent types. Along the way, we’ll learn about related concepts such as abstract type members and dependent method types. While these words might sound intimidating (including to this presenter!), they represent simple concepts useful in solving real-world problems.

Session length

40 minutes

Language of the presentation

English

Target audience

Intermediate: Requires a basic knowledge of the area

Who is your session intended to

Anyone interested in modelling real-world data while maintaining type-safety
Anyone curious about path-dependent types
Anyone who wants to see production, open-source code that brings it all together

Speaker

David van Geest (PagerDuty, Inc.)

• flatMap(Oslo) 2018 - https://www.youtube.com/watch?v=DRxLFWmvJ8A
• Scala Up North 2016 - https://www.youtube.com/watch?v=-4iaDd2RBSI

Contributes

• Arrivals - https://github.com/PagerDuty/arrivals