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• Byte

Byte-fix

Fixer for byte.

Signature

(byte-fix x) → fixed-x

Arguments

x — Guard (bytep x).

Returns

fixed-x — Type (bytep fixed-x).

Definitions and Theorems

Function: byte-fix

(defun byte-fix (x)
  (declare (xargs :guard (bytep x)))
  (mbe :logic (if (bytep x) x 0) :exec x))

Theorem: bytep-of-byte-fix

(defthm bytep-of-byte-fix
  (b* ((fixed-x (byte-fix x)))
    (bytep fixed-x))
  :rule-classes :rewrite)

Theorem: byte-fix-when-bytep

(defthm byte-fix-when-bytep
  (implies (bytep x)
           (equal (byte-fix x) x)))