{}:

{
corePrograms = { htop.enable = true; };
}

# this filename: coresimple.nix
# from within the repl if I load this and try to access corePrograms I get:
# nix-repl> (import ./coresimple.nix)
# «lambda @ /home/cody/my-emacs-everywhere-master/nixpkgs/coresimple.nix:1:1»

# nix-repl> (import ./coresimple.nix).corePrograms
# error: value is a function while a set was expected, at (string):1:1