G-Golf High Level API modules are defined in the hl-api
subdirectory, such as (g-golf hl-api gobject).
Where you may load these modules individually, the easiest way to use
the G-Golf High Level API is to import the hl-api module: it
imports and re-exports the public interface of (oop goops), some G-Golf
support modules and all G-Golf High Level API modules:
(use-modules (g-golf hl-api))
As stated in the introduction, G-Golf high level API (main) objective is to make (imported) GOBject classes and methods available using GOOPS, the Guile Object Oriented System (see GOOPS in The GNU Guile Reference Manual), in a way that is largely inspired by Guile-Gnome.