Dockerfile-class: An S4 class to represent a Dockerfile
In o2r-project/containerit: Package R in Docker Containers

An S4 class to represent a Dockerfile

The entrypoint and cmd are provided outside of instructions, as only one of them takes effect. If Cmd or Entrypoint instructions are provided as part of the regular instructions, they appear in the Dockerfile but have no effect.

an object of class Dockerfile

image: the base image, used in the FROM statement (character)
maintainer: a maintainer label or an object of class maintainer (the latter is debrecated)
instructions: an ordered list of instructions in the Dockerfile (list of character)
entrypoint: the entrypoint instruction applied to the container
cmd: the default cmd instruction applied to the container