An API for efficient and convenient construction of vectors. It provides the composable Builder abstraction, which has instances of the Monoid and Semigroup classes.

First you use the Builder abstraction to specify the structure of the vector. Then you execute the builder to produce the output vector.

The following code shows how you can efficiently concatenate different datastructures into a single immutable vector:

import qualified Data.Vector as A
import qualified VectorBuilder.Builder as B
import qualified VectorBuilder.Vector as C


myVector :: A.Vector a -> [a] -> a -> A.Vector a
myVector vector list element =
  C.build builder
  where
    builder =
      B.vector vector <>
      foldMap B.singleton list <>
      B.singleton element