Re: useful things with nnselect

[Andrew Cohen <acohen@ust.hk>]

>>>>> "ESF" == Eric S Fraga <e.fraga@ucl.ac.uk> writes:

[...]

    ESF> Thank you for this.  Very interesting.  I have a setup that has
    ESF> some similarity to yours, but obviously without using nnselect:
    ESF> using virtual groups and some splitting.  I will check nnselect
    ESF> out.

Before nnselect that is probably very similar to what I did. With
nnselect I can be much more fine-grained than I can with splitting and
combining, and I can do it on the fly. Let me know how it goes and if
you need any tips.

Oh, forgot to mention that (not surprisingly) nnselect can replace
nnvirtual. You just make an nnselect group with an nnselect-function
like the following (just hacked this together but it worked in one
simple test :)) and nnselect-args containing the groups you want to
combine:

(defun my-virtual (groups)
    (let ((limit 1000))
      (apply #'vconcat
	     (mapcar
	      #'(lambda (group)
		  (pcase-let ((`(,min . ,max) (gnus-active group))
			      (value))
		    (when (> (- max min) limit) (setq min (- max limit)))
		    (dotimes (number (1+ (- max min)) value)
		      (push  (vector group (+ min number) 1)
			     value))
		    (nreverse value)))
	      groups))))

(I have put an artificial limit on the size of the group since some of
my groups have hundreds of thousands of messages, and loading this many
headers is unbearably slow. But you can easily increase this beyond 1000
without too much trouble).