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• Fast-alists

Hons-dups-p1

Basic duplicates check; table is a fast alist that associates already-seen elements with t.

Definitions and Theorems

Function: hons-dups-p1

(defun hons-dups-p1 (l tab)
  (declare (xargs :guard t))
  (cond ((atom l) (ansfl nil tab))
        ((hons-get (car l) tab) (ansfl l tab))
        (t (hons-dups-p1 (cdr l)
                         (hons-acons (car l) t tab)))))