		Search-engine friendly clone of the ACL2 documentation.

Symbol

Symbol-fix

Fixing function for symbol structures.

Signature
(symbol-fix x) → new-x
Arguments: x — Guard (symbolp x).
Returns: new-x — Type (symbolp new-x).

Definitions and Theorems

Function: symbol-fix$inline

(defun symbol-fix$inline (x)
  (declare (xargs :guard (symbolp x)))
  (let ((__function__ 'symbol-fix))
    (declare (ignorable __function__))
    (mbe :logic
         (case (symbol-kind x)
           (:terminal (b* ((get (nfix x))) get))
           (:nonterminal (b* ((get (rulename-fix x))) get)))
         :exec x)))

Theorem: symbolp-of-symbol-fix

(defthm symbolp-of-symbol-fix
  (b* ((new-x (symbol-fix$inline x)))
    (symbolp new-x))
  :rule-classes :rewrite)

Theorem: symbol-fix-when-symbolp

(defthm symbol-fix-when-symbolp
  (implies (symbolp x)
           (equal (symbol-fix x) x)))

Function: symbol-equiv$inline

(defun symbol-equiv$inline (acl2::x acl2::y)
  (declare (xargs :guard (and (symbolp acl2::x)
                              (symbolp acl2::y))))
  (equal (symbol-fix acl2::x)
         (symbol-fix acl2::y)))

Theorem: symbol-equiv-is-an-equivalence

(defthm symbol-equiv-is-an-equivalence
  (and (booleanp (symbol-equiv x y))
       (symbol-equiv x x)
       (implies (symbol-equiv x y)
                (symbol-equiv y x))
       (implies (and (symbol-equiv x y)
                     (symbol-equiv y z))
                (symbol-equiv x z)))
  :rule-classes (:equivalence))

Theorem: symbol-equiv-implies-equal-symbol-fix-1

(defthm symbol-equiv-implies-equal-symbol-fix-1
  (implies (symbol-equiv acl2::x x-equiv)
           (equal (symbol-fix acl2::x)
                  (symbol-fix x-equiv)))
  :rule-classes (:congruence))

Theorem: symbol-fix-under-symbol-equiv

(defthm symbol-fix-under-symbol-equiv
  (symbol-equiv (symbol-fix acl2::x)
                acl2::x)
  :rule-classes (:rewrite :rewrite-quoted-constant))

Theorem: equal-of-symbol-fix-1-forward-to-symbol-equiv

(defthm equal-of-symbol-fix-1-forward-to-symbol-equiv
  (implies (equal (symbol-fix acl2::x) acl2::y)
           (symbol-equiv acl2::x acl2::y))
  :rule-classes :forward-chaining)

Theorem: equal-of-symbol-fix-2-forward-to-symbol-equiv

(defthm equal-of-symbol-fix-2-forward-to-symbol-equiv
  (implies (equal acl2::x (symbol-fix acl2::y))
           (symbol-equiv acl2::x acl2::y))
  :rule-classes :forward-chaining)

Theorem: symbol-equiv-of-symbol-fix-1-forward

(defthm symbol-equiv-of-symbol-fix-1-forward
  (implies (symbol-equiv (symbol-fix acl2::x)
                         acl2::y)
           (symbol-equiv acl2::x acl2::y))
  :rule-classes :forward-chaining)

Theorem: symbol-equiv-of-symbol-fix-2-forward

(defthm symbol-equiv-of-symbol-fix-2-forward
  (implies (symbol-equiv acl2::x (symbol-fix acl2::y))
           (symbol-equiv acl2::x acl2::y))
  :rule-classes :forward-chaining)

Theorem: symbol-kind$inline-of-symbol-fix-x

(defthm symbol-kind$inline-of-symbol-fix-x
  (equal (symbol-kind$inline (symbol-fix x))
         (symbol-kind$inline x)))

Theorem: symbol-kind$inline-symbol-equiv-congruence-on-x

(defthm symbol-kind$inline-symbol-equiv-congruence-on-x
  (implies (symbol-equiv x x-equiv)
           (equal (symbol-kind$inline x)
                  (symbol-kind$inline x-equiv)))
  :rule-classes :congruence)