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Type-Driven Development in Idris — Edwin Brady

Scala World · 26K views · 2015-10-12 · 46:36

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Overview

Edwin Brady, creator of Idris, introduces type-driven development in a dependently typed language. He shows types being written first and programs derived with interactive editing, then extends beyond simple examples to programs that interact with users and networks.

On Hacker News

HN points to it as a demonstration of type-directed editing with typed holes, which some see as a likely future of programming.

Recommended by 1 HN people across 1 months · HN mentions 2019–2024

Topics

Programming language designFunctional programmingLogic & formal methods
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idristype-driven developmenttyped holesinteractive editing

What people said

still_grokking · 2023-01 · Recommendation

> Basically, your IDE writes more of the code for you. I think this was, in general, a dead end in language research for various reasons, […] I think language researchers would strongly disagree. Something like that is likely the future of programming! For example: [VIDEO] From the video description: > In Idris, types are a first class language construct, meaning that they can be manipulated and computed like any other language construct. It encourages a type-driven style of development, in which programmers give types first and use interactive editing tools to derive programs.

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dietr1ch · 2024-11 · Reference

Brady has a presentation about Idris where he shows Type-Driven development (where you write code that could typecheck with some holes and you get the compiler to help you figure out the missing types for your "whatever/something" untyped variables) [VIDEO]

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nequo · 2022-11 · Reference

Thinking in types and type relations sounds to me like Rule 5 taken to its logical conclusion. Types are your data structures, and they guide how you write your functions. Agda[1] and Idris[2] turn this idea into interactive editing with typed holes. You put a "?" in the code and the compiler fills the hole in for you based on the type that it infers for it. Haskell has a less expressive type system but it also has typed holes and Wingman[3] extends the Haskell Language Server to use them for interactive editing. [1] [LINK] [2] [VIDEO] [3] [LINK]

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Sources

Video by Scala World, played through YouTube.

Data and selection notes

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