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Unique-variables

Var-unique-vars

Check that a variable is unique.

Signature
(var-unique-vars var allvars) → new-allvars
Arguments: var — Guard (identifierp var).; allvars — Guard (identifier-setp allvars).
Returns: new-allvars — Type (identifier-set-resultp new-allvars).

Check that it does not occur in the set of all variables found so far, and add it to that set if successful.

This is very similar to add-var, but it has a different purpose.

Definitions and Theorems

Function: var-unique-vars

(defun var-unique-vars (var allvars)
  (declare (xargs :guard (and (identifierp var)
                              (identifier-setp allvars))))
  (let ((__function__ 'var-unique-vars))
    (declare (ignorable __function__))
    (if (in (identifier-fix var)
            (identifier-set-fix allvars))
        (reserrf (list :non-unique-var (identifier-fix var)))
      (insert (identifier-fix var)
              (identifier-set-fix allvars)))))

Theorem: identifier-set-resultp-of-var-unique-vars

(defthm identifier-set-resultp-of-var-unique-vars
  (b* ((new-allvars (var-unique-vars var allvars)))
    (identifier-set-resultp new-allvars))
  :rule-classes :rewrite)

Theorem: var-unique-vars-to-set-insert

(defthm var-unique-vars-to-set-insert
  (b* ((allvars1 (var-unique-vars var allvars)))
    (implies (not (reserrp allvars1))
             (equal allvars1
                    (insert (identifier-fix var)
                            (identifier-set-fix allvars))))))

Theorem: var-unique-vars-of-identifier-fix-var

(defthm var-unique-vars-of-identifier-fix-var
  (equal (var-unique-vars (identifier-fix var)
                          allvars)
         (var-unique-vars var allvars)))

Theorem: var-unique-vars-identifier-equiv-congruence-on-var

(defthm var-unique-vars-identifier-equiv-congruence-on-var
  (implies (identifier-equiv var var-equiv)
           (equal (var-unique-vars var allvars)
                  (var-unique-vars var-equiv allvars)))
  :rule-classes :congruence)

Theorem: var-unique-vars-of-identifier-set-fix-allvars

(defthm var-unique-vars-of-identifier-set-fix-allvars
  (equal (var-unique-vars var (identifier-set-fix allvars))
         (var-unique-vars var allvars)))

Theorem: var-unique-vars-identifier-set-equiv-congruence-on-allvars

(defthm var-unique-vars-identifier-set-equiv-congruence-on-allvars
  (implies (identifier-set-equiv allvars allvars-equiv)
           (equal (var-unique-vars var allvars)
                  (var-unique-vars var allvars-equiv)))
  :rule-classes :congruence)