spacebat/insert.el

Created April 8, 2013 22:57

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Insert an element before another in a list

Raw

+(let ((data '((a 1 2 3)(c 5 6 7)))
+             (insert '(b x y z)))
+         (loop for prev on data
+               for next on (cdr data)
+               if (and next (eq (caar next) 'c))
+               do (let ((newcons (cons insert next)))
+                    (setcdr prev newcons)))
+         data)

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