Use a fst file as a container for an ALTREP vector

[MarcusKlik]

R 3.5.0 brings some features from the ALTREP framework. One of those features is that the actual vector data can be stored in an alternative structure or location. Such a structure could be a fst file.

Because fst provides random access to stored vectors, it could be the ideal ALTREP container for vector data.

[MarcusKlik]

A reference to some features of the ALTREP framework can be found here.

[MarcusKlik]

The simplemmap package can be used to learn what's needed to implement a vector with it's data stored in a fst file.