• Top
  • Documentation
  • Books
  • Recursion-and-induction
  • Boolean-reasoning
  • Debugging
  • Projects
  • Std
    • Std/lists
    • Std/alists
    • Obags
    • Std/util
    • Std/strings
    • Std/io
    • Std/osets
    • Std/system
    • Std/basic
      • Maybe-stringp
      • Maybe-natp
      • Two-nats-measure
      • Impossible
      • Nat-list-measure
      • Bytep
      • Maybe-posp
      • Nibblep
      • Mbt$
      • Organize-symbols-by-pkg
      • Organize-symbols-by-name
      • Good-valuep
      • Lnfix
      • Streqv
      • Chareqv
      • Symbol-package-name-non-cl
      • Std/basic-extensions
      • Arith-equivs
      • Induction-schemes
      • Maybe-integerp
      • Char-fix
      • Symbol-package-name-lst
      • Pos-fix
      • Maybe-bitp
      • Good-pseudo-termp
      • Str-fix
      • Maybe-string-fix
      • Lifix
      • Bfix
      • Std/basic/if*
      • Impliez
      • Tuplep
      • Std/basic/symbol-name-lst
      • Std/basic/intern-in-package-of-symbol
      • Lbfix
      • True
      • Std/basic/member-symbol-name
      • False
    • Std/typed-lists
    • Std/bitsets
    • Std/testing
    • Std/typed-alists
    • Std/stobjs
    • Std-extensions
  • Proof-automation
  • Macro-libraries
  • ACL2
  • Interfacing-tools
  • Hardware-verification
  • Software-verification
  • Testing-utilities
  • Math

• Std/basic
• Std/basic-extensions
• Maybe-stringp

Maybe-string-fix

Fixer for maybe-stringp.

Signature

(maybe-string-fix x) → fixed-x

Arguments

x — Guard (maybe-stringp x).

Returns

fixed-x — Type (maybe-stringp fixed-x).

Definitions and Theorems

Function: maybe-string-fix

(defun maybe-string-fix (x)
       (declare (xargs :guard (maybe-stringp x)))
       (mbe :logic (if (maybe-stringp x) x nil)
            :exec x))

Theorem: maybe-stringp-of-maybe-string-fix

(defthm maybe-stringp-of-maybe-string-fix
        (b* ((fixed-x (maybe-string-fix x)))
            (maybe-stringp fixed-x))
        :rule-classes :rewrite)

Theorem: maybe-string-fix-when-maybe-stringp

(defthm maybe-string-fix-when-maybe-stringp
        (implies (maybe-stringp x)
                 (equal (maybe-string-fix x) x)))