List of current apt sources?

[The Wanderer <wanderer@fastmail.fm>]

Looking in /etc/apt/sources.list tells you what sources will be active after the
next 'apt-get update' (assuming all of them are valid).

Is there any way to get a list of what sources are *currently* active, i.e., the
ones which were in sources.list during the *most recent* successful 'apt-get
update'?

That seems like information which would have to exist for apt-get to work the
way it does, but at a glance I don't see any indication in the man pages on how
to access it.

--
   The Wanderer

Warning: Simply because I argue an issue does not mean I agree with any
side of it.

Every time you let somebody set a limit they start moving it.
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