Definitions for "Functor"
an expression that specifies the components of a module
an integer, a float, a string, a name, a compound term, or a higher-order term
an ML program module takes the signature of another module as an argument
a kind of map between categories
a structure preserving map of categories, defined exactly analogously to group homomorphisms
In category theory, a functor is a special type of mapping between categories. Functors can be thought of as morphisms in the category of small categories.
a structured collection (or container) type with a method (fmap) that accepts a method and applies that method to the members of the collection yielding an isomorphic collection of values of a (possibly) new type
The name of a predicate or structure.
a function that can be manipulated as an object, or an object representing a single, generic function
an object that can be called via operator()
an object that encapsulates a function or expression
a class that defines a function-call operator
a class that defines the '()' operator