Conflicts vs Replaces vs Provides

[Harald Dunkel <harri@afaics.de>]

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Hi folks,

I found this in debian/control for libgl1-mesa-glx:

	:
	Conflicts: libgl1, libgl1-mesa-dri (<< 6.4.0)
	Replaces: libgl1, libgl1-mesa-dri (<< 6.4.0)
	Provides: libgl1
	:

This looks weird to me. How can it replace and conflict with
its own virtual package name? Doesn't this mean that no other
packages providing libgl1 can be installed, making
/etc/alternatives useless?

Any helpful comment would be highly appreciated.


Regards

Harri
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