bug#73431: Add `setf` support for `stream.el` in ELPA

[Philip Kaludercic <philipk@posteo.net>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> Currently, using `(setf (seq-elt STREAM 0) VAL)` silently fails, because 
>> it treats the stream as a list, breaking the stream.
>
> Sounds like a bug, indeed.  But I'd rather fix it by making it fail
> cleanly, to preserve the (current) immutability of streams (at least
> until we decide that there's a good reason for streams to be mutable).

One exception to the immutability of stream might be buffers?  Or at
least it seems like something that would be useful to have.

>> On the desire for mutability, there is the included macro `stream-pop`.
>
> `stream-pop` does not mutate the stream.  It only mutates a local
> variable (which holds a (reference to a) stream).
>
>
>         Stefan
>

-- 
	Philip Kaludercic on siskin