Functional Enumeration of Algebraic Types

feat is a library that offers support for counting, enumerating, and sampling objects of a certain kind, such as (say) the inhabitants of an algebraic data type.

Feat was inspired by the paper Feat: Functional Enumeration of Algebraic Types by Jonas Duregård, Patrik Jansson and Meng Wang (2012). It can perhaps be compared with the Haskell library testing-feat, although a detailed comparison has not been carried out.

The packages feat and feat-num offer the same API: you should use either feat or feat-num, not both. feat relies on the big integer library zarith, whereas feat-num relies on the legacy library num. Both packages offer the same API: the main module, named Feat or FeatNum, offers three submodules named Num, IFSeq, and Enum.