Data.Logic.Classes.Arity

Documentation

class Arity p where

A class that characterizes how many arguments a predicate or function takes. Depending on the context, a result of Nothing may mean that the arity is undetermined or unknown. However, even if this returns Nothing, the same number of arguments must be passed to all uses of a given predicate or function.

Methods

arity :: p -> Maybe Int

Instances

Arity String

Arity PredName