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• Dec-digit-char

Dec-digit-char-fix

Fixer for dec-digit-char.

Signature

(dec-digit-char-fix x) → fixed-x

Arguments

x — Guard (dec-digit-char-p x).

Returns

fixed-x — Type (dec-digit-char-p fixed-x).

Definitions and Theorems

Function: dec-digit-char-fix

(defun dec-digit-char-fix (x)
  (declare (xargs :guard (dec-digit-char-p x)))
  (mbe :logic (if (dec-digit-char-p x) x #\0)
       :exec x))

Theorem: dec-digit-char-p-of-dec-digit-char-fix

(defthm dec-digit-char-p-of-dec-digit-char-fix
  (b* ((fixed-x (dec-digit-char-fix x)))
    (dec-digit-char-p fixed-x))
  :rule-classes :rewrite)

Theorem: dec-digit-char-fix-when-dec-digit-char-p

(defthm dec-digit-char-fix-when-dec-digit-char-p
  (implies (dec-digit-char-p x)
           (equal (dec-digit-char-fix x) x)))