同じ年月は(ry

http://cadr.g.hatena.ne.jp/g000001/20101113/1289653556
http://cadr.g.hatena.ne.jp/lkozima/20101113/1289661114
をArcで。

(= *ym* '("2009-11" "2009-01" "2010-01" "2010-12" "2010-01"
	  "2010-04" "2010-01" "2010-12" "2010-12" "2010-04"))

(pr:sort (fn (a b) (> a.0 b.0)) (tablist:counts *ym*))

countsはxyzzyでも使えるようにしておくと吉。実装例

(w/infile (is "C:/Users/yz/quicklisp/dists/quicklisp/systems.txt")
  (read-line is)
  (firstn 20
	  (sort (tablist (counts (drain (read is nil))))
		#'> :key #'cadr)))
; -> ((cl-glfw 145) (cl-glfw-opengl 141) (hu.dwim.asdf 121) (cffi 89) (cl-ppcre 60) (mcclim 60) (alexandria 59) (iterate 45) (hu.dwim.util 42) (lispbuilder 36) (bordeaux-threads 36) (gbbopen 35) (cxml 33) (hu.dwim.wui 32) (closer-mop 32) (lift 31) (flexi-streams 26) (metabang-bind 24) (hu.dwim.def 24) (babel 24))

arcから色々パクっておくと*scratch*で雑務を片す時にとても便利