Type Alias Transform 

pub type Transform<F, A> = PostAggregation<F, fn(Aggregation<F>) -> A>;

A post-aggregation of a function pointer.

This type definition describes a stateless and pure transform with a type name that can be spelled in any context (i.e., no closure or other unnameable types occur).

Aliased Type

pub struct Transform<F, A> { /* private fields */ }