“Open Data Types and Open Functions” in Haskell

Question

Is there an existing implementation of the open semantics defined in the paper Open Data Types and Open Functions ? As a GHC extension, as Template Haskell, as part of some other Haskell compiler, as a preprocessor, etc. The paper was published in 2006, and it claims to be simple.

I need data extensibility for a few core types in a project I'm working on. But I don't want to lift every constructor of the open datum to a type, and every open function to a class.

Answer 1

虽然与open相比它是相当重量级的，但通常的方法是引入一种类似于“点菜”论文的机制： http ： //citeseerx.ist.psu.edu/viewdoc/summary？ DOI = 10.1.1.101.4131