John Wiegley <jwiegley@gmail.com> writes:

> If that's the case, then yes, it should be in core. I'm personally a bit
> surprised that a library of this nature is in ELPA,

In the case of seq.el, it's for backward-compatibility.  It made it
possible for instance for CIDER devs to start using it while Emacs 25 is
still in progress.

> unless it was being
> provided and actively maintained by a non-core developer.

IIRC, Stefan thought that having stream.el in the ELPA meant more sense
at least until people start using it more.

Nico