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• Equivalences

Str-fix

Coerce to a string.

(str-fix x) is the identity on stringps, or returns the empty string, "", for any non-string.

This is similar to other fixing functions like fix and nfix. See also streqv.

Definitions and Theorems

Function: str-fix$inline

(defun str-fix$inline (x)
  (declare (xargs :guard t))
  (if (stringp x) x ""))

Theorem: stringp-of-str-fix

(defthm stringp-of-str-fix
  (stringp (str-fix x))
  :rule-classes :type-prescription)

Theorem: str-fix-default

(defthm str-fix-default
  (implies (not (stringp x))
           (equal (str-fix x) "")))

Theorem: str-fix-when-stringp

(defthm str-fix-when-stringp
  (implies (stringp x)
           (equal (str-fix x) x)))