GNUInstallDirs: Document the ${dir} variable or Extend/Update GNUInstallDirs_get_install_dir() macro
The GNUInstallDirs_get_absolute_install_dir()
macro depends importantly on the value of ${dir}
. It seems that the documentation should be updated to describe this ${dir}
dependency.
Maybe better, the macro could be updated in a backward compatible way so as to accept a third optional argument that specifies the value of dir
to use.