Trait-Constrained Enums in Rust
Simulating Haskell-style GADTs with phantom witnesses and specialisation.
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( )
2025
2020
Announcing generic-optics (& generic-lens 2.0.0.0)
generic-lens gets a new interface.
2019
Opaque constraint synonyms
Hiding internal details of constraint synonyms.
Tripping up type inference
Improving code readability by enforcing type annotations.
Most underrated vim features: C-a
In which I present a hidden gem in the vim text editor.
Global Implicit Parameters
Exploiting GHC internals to define top-level implicit parameters.
2018
Detecting the undetectable: custom type errors for stuck type families
Stuck type families are notorious for producing puzzling type errors. In this post I present a technique for detecting and reporting them.
Parsing type-level strings in Haskell
A technique for manipulating Symbols in GHC for type-level programming.
2017
Deriving Bifunctor with Generics
A techinque for approximating Generic2 with only the Generic type class.
Announcing generic-lens 0.5.0.0
Deriving lenses generically
Well-typed printfs cannot go wrong
Writing a simple parser of type-level symbols in PureScript 0.12
2015
Time travel in Haskell for dummies
Some interesting consequences of lazy evaluation.