• Top
  • Documentation
  • Books
  • Boolean-reasoning
  • Projects
  • Debugging
  • Std
    • Std/lists
    • Std/alists
    • Obags
    • Std/util
    • Std/strings
      • Pretty-printing
      • Printtree
      • Base64
      • Charset-p
      • Strtok!
      • Cases
      • Concatenation
      • Html-encoding
      • Character-kinds
        • Letter/digit/uscore/dollar-char-p
        • Letter/digit/uscore/dash-char-p
        • Letter/uscore/dollar-char-p
        • Letter/digit/uscore-char-p
        • Letter/digit/dash-char-p
        • Letter-char-p
        • Letter/digit-char-p
        • Lcletter/digit-char-p
        • Ucletter/digit-char-p
        • Printable-char-p
          • Printable-charlist-p
          • Printable-chars
        • Nondigit-char-p
        • Ucletter-char-p
        • Lcletter-char-p
      • Substrings
      • Strtok
      • Equivalences
      • Url-encoding
      • Lines
      • Explode-implode-equalities
      • Ordering
      • Numbers
      • Pad-trim
      • Coercion
      • Std/strings/digit-to-char
      • Substitution
      • Symbols
    • Std/io
    • Std/osets
    • Std/basic
    • Std/system
    • Std/typed-lists
    • Std/bitsets
    • Std/testing
    • Std/typed-alists
    • Std/stobjs
  • Proof-automation
  • Macro-libraries
  • ACL2
  • Interfacing-tools
  • Hardware-verification
  • Software-verification
  • Math
  • Testing-utilities

• Character-kinds

Printable-char-p

Recognize printable ASCII characters, i.e. spaces and visible ASCII characters.

Definitions and Theorems

Function: printable-char-p

(defun printable-char-p (x)
  (declare (xargs :guard t))
  (and (characterp x)
       (b* ((code (char-code x)))
         (and (<= 32 code) (<= code 126)))))

Theorem: booleanp-of-printable-char-p

(defthm booleanp-of-printable-char-p
  (booleanp (printable-char-p x))
  :rule-classes :type-prescription)

Theorem: characterp-when-printable-char-p

(defthm characterp-when-printable-char-p
  (implies (printable-char-p x)
           (characterp x))
  :rule-classes :compound-recognizer)

Subtopics

Printable-charlist-p

(printable-charlist-p x) recognizes lists where every element satisfies printable-char-p.

Printable-chars

A character set for printable-char-p.