This has been discussed a few times.

What about letting packages provide a feature or capability and then other
packages could depend on that feature/capability instead of a specific
package dependency?

One idea would be for mailwrapper: it needs a sendmail. Then postfix,
exim, sendmail could all say they PROVIDE a sendmail.

Debian and some other package systems provide this.

It could also be used if needing an lpr.

I was thinking about this again this week, because I was wondering if it
would be possible to plug-and-play different X11 library implementations
-- without having to rebuild nor reinstall the packages using X. (I am
moving from XFree86 to Xorg.)

Any comments would be appreciated.

 Jeremy C. Reed

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