This abstraction allows to create chunks of various types out of an
input stream. One possible accumulator is the `Token` accumulator which
generates the token stream.

Leveraging this abstraction, we can then implement a pipe that builds
directly AST values instead of having intermediate `Token`
representation.

Inspired by the `Facade` abstraction from jawn, we can build the AST
directly, without emitting intermediate tokens, which makes it faster.

The fact that it now returs `Unit` makes it clearer it is side
effectful.