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Tailrec-input-processing

Tailrec-variantp

Variants of the tail recursion transformation.

This is an ordinary std::defenum.

Function: tailrec-variantp

(defun tailrec-variantp (x)
  (declare (xargs :guard t))
  (or (eq x ':assoc)
      (eq x ':assoc-alt)
      (eq x ':monoid)
      (eq x ':monoid-alt)))

Theorem: type-when-tailrec-variantp

(defthm type-when-tailrec-variantp
  (implies (tailrec-variantp x)
           (if (symbolp x)
               (if (not (equal x 't))
                   (not (equal x 'nil))
                 'nil)
             'nil))
  :rule-classes :compound-recognizer)