• Top
  • Documentation
  • Books
  • Boolean-reasoning
  • Projects
  • Debugging
  • Std
  • Proof-automation
  • Macro-libraries
  • ACL2
    • Theories
    • Rule-classes
    • Proof-builder
    • Recursion-and-induction
    • Hons-and-memoization
    • Events
    • Parallelism
    • History
    • Programming
      • Defun
      • Declare
      • System-utilities
      • Stobj
      • State
      • Mutual-recursion
      • Memoize
      • Mbe
      • Io
      • Defpkg
      • Apply$
      • Loop$
      • Programming-with-state
      • Arrays
      • Characters
        • Character-listp
        • Characterp
        • Coerce
        • Digit-char-p
        • Code-char
        • Char-code
        • Char-upcase
        • Char-downcase
        • Standard-char-p
        • Char
        • Alpha-char-p
        • Explode-nonnegative-integer
        • Upper-case-p
        • Lower-case-p
        • Explode-atom
        • Char-equal
        • Digit-to-char
        • Char<
        • Char>=
        • Make-character-list
        • Char>
        • Char<=
        • Standard-char-listp
        • Character-alistp
        • Standard-char-p+
        • Chars-upcase-gen
        • Chars-downcase-gen
        • Char-upcase-gen
        • Char-downcase-gen
      • Time$
      • Loop$-primer
      • Fast-alists
      • Defconst
      • Defmacro
      • Evaluation
      • Guard
      • Equality-variants
      • Compilation
      • Hons
      • ACL2-built-ins
      • Developers-guide
      • System-attachments
      • Advanced-features
      • Set-check-invariant-risk
      • Numbers
      • Irrelevant-formals
      • Efficiency
      • Introduction-to-programming-in-ACL2-for-those-who-know-lisp
      • Redefining-programs
      • Lists
      • Invariant-risk
      • Errors
      • Defabbrev
      • Conses
      • Alists
      • Set-register-invariant-risk
      • Strings
      • Program-wrapper
      • Get-internal-time
      • Basics
      • Packages
      • Oracle-eval
      • Defmacro-untouchable
      • Primitive
      • <<
      • Revert-world
      • Unmemoize
      • Set-duplicate-keys-action
      • Symbols
      • Def-list-constructor
      • Easy-simplify-term
      • Defiteration
      • Fake-oracle-eval
      • Defopen
      • Sleep
    • Operational-semantics
    • Real
    • Start-here
    • Debugging
    • Miscellaneous
    • Output-controls
    • Macros
    • Interfacing-tools
  • Interfacing-tools
  • Hardware-verification
  • Software-verification
  • Math
  • Testing-utilities

• Characters
• Alists
• ACL2-built-ins

Character-alistp

Recognizer for association lists with characters as keys

(Character-alistp x) is true if and only if x is a list of pairs of the form (cons key val) where key is a characterp.

Function: character-alistp

(defun character-alistp (x)
  (declare (xargs :guard t))
  (cond ((atom x) (eq x nil))
        (t (and (consp (car x))
                (characterp (car (car x)))
                (character-alistp (cdr x))))))