# Original author :     Alastair Tse <liquidx@gentoo.org> (03 Oct 2003)

# @BLURB:  Creates symlink to the latest version of multiple slotted packages.

# @DESCRIPTION:

# When a package is SLOT'ed, very often we need to have a symlink to the

# latest version. However, depending on the order the user has merged them,

# more often than not, the symlink maybe clobbered by the older versions.

#

# This eclass provides a convenience function that needs to be given a

# list of alternatives (descending order of recent-ness) and the symlink.

# It will choose the latest version it can find installed and create

# the desired symlink.

#

# There are two ways to use this eclass. First is by declaring two variables

# $SOURCE and $ALTERNATIVES where $SOURCE is the symlink to be created and

# $ALTERNATIVES is a list of alternatives. Second way is the use the function

# alternatives_makesym() like the example below.

# @EXAMPLE:

# pkg_postinst() {

#     alternatives_makesym "/usr/bin/python" "/usr/bin/python2.3" "/usr/bin/python2.2"

# }

#

# The above example will create a symlink at /usr/bin/python to either

# /usr/bin/python2.3 or /usr/bin/python2.2. It will choose python2.3 over

# python2.2 if both exist.

#

# Alternatively, you can use this function:

#

# pkg_postinst() {

#    alternatives_auto_makesym "/usr/bin/python" "/usr/bin/python[0-9].[0-9]"

# }

#

# This will use bash pathname expansion to fill a list of alternatives it can

# link to. It is probably more robust against version upgrades. You should

# consider using this unless you are want to do something special.

# @ECLASS-VARIABLE: SOURCE

# @DESCRIPTION:

# The symlink to be created

# @ECLASS-VARIABLE: ALTERNATIVES

# @DESCRIPTION:

# The list of alternatives

# @FUNCTION: alternatives_auto_makesym

# @DESCRIPTION:

# @FUNCTION: alternatives_pkg_postrm

# @DESCRIPTION:

# The alternatives pkg_postrm, this function will be exported