defines a path config option CONFNAME. DEFAULT is the default value of this option. DESCRIPTION is the short description of this option which is used from '--help' global option.
defines a bool config option CONFNAME. DEFAULT is the default value of this option. DESCRIPTION is the short description of this option which is used from '--help' global option.
set default value of config CONFNAME to VAL. If CONFNAME is a bool config, VAL should be boolean. Else VAL should be a String.
removes config entry CONFNAME from the installer completely. You must use this method at your own lisk. For example, 'remove_config("prefix")' causes fatal error.
Returns the list of package names. This method raises RuntimeError if called in the single package archive.
Set the ordered list of installing package names. This method raises RuntimeError if called in the single package archive.