eselect
Works:
eselect bashcomp enable --global ri
Silently fails:
eselect bashcomp enable ri --global
Reason: (/usr/share/eselect/modules/bashcomp.eselect)
do_enable() {
#...snip...
if [[ ${1} == "--global" ]] ; then
bcdir="${ROOT}/etc/bash_completion.d"
shift
fi
#...snip...
# ignore any unrecognized options
[[ ${bc} == --* ]] && continue
Always looks for --global as the first parameter, apparently. Bug? Not sure. This would be the second eselect-related bug I've noticed in the past two days, if so.

That's no more a bug in eselect than a bug in a C program is a bug in GCC.
Nothing to do with eselect itself, I know. Just a module. Loose usage of terminology on my part.
Bug or not, the second method, which doesn't work, seems more natural to me anyway. Perhaps it should accept both.