>>>>> Drew Adams <drew.adams@oracle.com> writes:

 >> Given that switch-to-buffer returns its argument, /and/ given that
 >> mapc returns the sequence it’s given, I suggest that the
 >> (mapcar 'switch-to-buffer LIST) forms in lisp/files.el be replaced
 >> with (mapc 'switch-to-buffer LIST), – if only to avoid the
 >> unnecessary consing when the list is effectively copied in the
 >> mapcar case.

 >> The lists mapcar is applied to in such cases are returned from
 >> find-file-noselect, and so, as it seems, are “fresh” ones anyway.

 > Not a good idea, IMHO.

 > It's not just about performance; it's about coding style.

 > By using `mapcar' you are signaling that you are interested in the
 > return values of the argument function (and of course the resulting
 > list of them).

 > By using `mapc' you are signaling that the values returned by the
 > argument function are unimportant (only its side effects are
 > significant).

	How do you signal that the values returned by the argument
	function are unimportant, /and/ that you’re interested in the
	/original/ list instead?

 > If you want to improve the performance, and that is the only change
 > you want to make, then please consider another approach.

	Please consider the patch MIMEd.  FWIW, it avoids one more cons
	in both find-file-other-window and find-file-other-frame.

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