##
# \file

# To each interface a set of caller functions exist, that take an instance
# of an object and then in turn call the implementation for the class of
# this object. If there is none within the class it looks into its
# parent class and so forth.
#
# This is somewhat similar to late binding in real OOP languages, but
# by far not so elaborated. This is not a real object oriented language
# and will surely never ever provide all features these have.
#
# That said it has proven very usefull for me to orgnize code and prevent
# code duplication.
#
# \author	Georg Hopp
#
# \copyright
# Copyright © 2014 Georg Hopp
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

has_class() {
	if [ 1 -ne $# ]
	then
		logger -p syslog.err 'has_class: no class given'
		exit 1
	fi

	local CHECK=" ${CLASSES}"
	test "${CHECK}" != "${CHECK% ${1} *}"
}

##
# add one or more classes given as arguments to this function
# Using ${@} here effectively eliminates multiple spaces between
# the classnames.
# A class might be defined multiple times...I don't eliminate these
# duplicates as this might involve calling uniq which is unneccesary
# overhead as I see no harm in duplicates now.
#
set_class() {
	[ -z "${CLASSES}" ] &&
		{ CLASSES="${@}"; export CLASSES; } ||
		CLASSES="${CLASSES} ${@}"
}

# vim: set ts=4 sw=4: