• Top
    • Documentation
    • Books
    • Recursion-and-induction
    • Boolean-reasoning
    • Debugging
    • Projects
    • Std
      • Std/lists
      • Std/alists
      • Obags
      • Std/util
      • Std/strings
        • Pretty-printing
        • Printtree
        • Base64
        • Charset-p
        • Strtok!
        • Cases
        • Concatenation
        • Html-encoding
        • Character-kinds
        • Substrings
        • Strtok
        • Equivalences
          • Charlisteqv
          • Icharlisteqv
            • Istreqv
            • Ichareqv
            • Streqv
            • Chareqv
            • Char-fix
            • Str-fix
          • Url-encoding
          • Lines
          • Ordering
          • Numbers
          • Pad-trim
          • Coercion
          • Std/strings-extensions
          • Std/strings/digit-to-char
          • Substitution
          • Symbols
        • Std/io
        • Std/osets
        • Std/system
        • Std/basic
        • 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
    • Equivalences
    • Cases

    Icharlisteqv

    Case-insensitive character-list equivalence test.

    Signature
    (icharlisteqv x y) → bool
    Arguments
    x — Guard (character-listp x).
    y — Guard (character-listp y).

    (icharlisteqv x y) determines if x and y are case-insensitively equivalent character lists. That is, x and y must have the same length and their elements must be ichareqv to one another.

    See also charlisteqv for a case-sensitive alternative.

    Definitions and Theorems

    Function: icharlisteqv

    (defun icharlisteqv (x y)
           (declare (xargs :guard (and (character-listp x)
                                       (character-listp y))))
           (let ((acl2::__function__ 'icharlisteqv))
                (declare (ignorable acl2::__function__))
                (if (consp x)
                    (and (consp y)
                         (ichareqv (car x) (car y))
                         (icharlisteqv (cdr x) (cdr y)))
                    (atom y))))

    Theorem: icharlisteqv-is-an-equivalence

    (defthm icharlisteqv-is-an-equivalence
            (and (booleanp (icharlisteqv x y))
                 (icharlisteqv x x)
                 (implies (icharlisteqv x y)
                          (icharlisteqv y x))
                 (implies (and (icharlisteqv x y)
                               (icharlisteqv y z))
                          (icharlisteqv x z)))
            :rule-classes (:equivalence))

    Theorem: charlisteqv-refines-icharlisteqv

    (defthm charlisteqv-refines-icharlisteqv
            (implies (charlisteqv x y)
                     (icharlisteqv x y))
            :rule-classes (:refinement))

    Theorem: icharlisteqv-implies-ichareqv-car-1

    (defthm icharlisteqv-implies-ichareqv-car-1
            (implies (icharlisteqv x x-equiv)
                     (ichareqv (car x) (car x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-cdr-1

    (defthm icharlisteqv-implies-icharlisteqv-cdr-1
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (cdr x) (cdr x-equiv)))
            :rule-classes (:congruence))

    Theorem: ichareqv-implies-icharlisteqv-cons-1

    (defthm ichareqv-implies-icharlisteqv-cons-1
            (implies (ichareqv a a-equiv)
                     (icharlisteqv (cons a x)
                                   (cons a-equiv x)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-cons-2

    (defthm icharlisteqv-implies-icharlisteqv-cons-2
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (cons a x)
                                   (cons a x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-equal-len-1

    (defthm icharlisteqv-implies-equal-len-1
            (implies (icharlisteqv x x-equiv)
                     (equal (len x) (len x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-list-fix-1

    (defthm icharlisteqv-implies-icharlisteqv-list-fix-1
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (list-fix x)
                                   (list-fix x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-ichareqv-nth-2

    (defthm icharlisteqv-implies-ichareqv-nth-2
            (implies (icharlisteqv x x-equiv)
                     (ichareqv (nth n x) (nth n x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-nthcdr-2

    (defthm icharlisteqv-implies-icharlisteqv-nthcdr-2
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (nthcdr n x)
                                   (nthcdr n x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-take-2

    (defthm icharlisteqv-implies-icharlisteqv-take-2
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (take n x)
                                   (take n x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-append-1

    (defthm icharlisteqv-implies-icharlisteqv-append-1
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (append x y)
                                   (append x-equiv y)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-append-2

    (defthm icharlisteqv-implies-icharlisteqv-append-2
            (implies (icharlisteqv y y-equiv)
                     (icharlisteqv (append x y)
                                   (append x y-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-rev-1

    (defthm icharlisteqv-implies-icharlisteqv-rev-1
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (rev x) (rev x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-revappend-2

    (defthm icharlisteqv-implies-icharlisteqv-revappend-2
            (implies (icharlisteqv y y-equiv)
                     (icharlisteqv (revappend x y)
                                   (revappend x y-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-revappend-1

    (defthm icharlisteqv-implies-icharlisteqv-revappend-1
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (revappend x y)
                                   (revappend x-equiv y)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-implies-icharlisteqv-make-character-list-1

    (defthm icharlisteqv-implies-icharlisteqv-make-character-list-1
            (implies (icharlisteqv x x-equiv)
                     (icharlisteqv (make-character-list x)
                                   (make-character-list x-equiv)))
            :rule-classes (:congruence))

    Theorem: icharlisteqv-when-not-consp-left

    (defthm icharlisteqv-when-not-consp-left
            (implies (not (consp x))
                     (equal (icharlisteqv x y) (atom y))))

    Theorem: icharlisteqv-when-not-consp-right

    (defthm icharlisteqv-when-not-consp-right
            (implies (not (consp y))
                     (equal (icharlisteqv x y) (atom x))))

    Theorem: icharlisteqv-of-cons-right

    (defthm icharlisteqv-of-cons-right
            (equal (icharlisteqv x (cons a y))
                   (and (consp x)
                        (ichareqv (car x) (double-rewrite a))
                        (icharlisteqv (cdr x)
                                      (double-rewrite y)))))

    Theorem: icharlisteqv-of-cons-left

    (defthm icharlisteqv-of-cons-left
            (equal (icharlisteqv (cons a x) y)
                   (and (consp y)
                        (ichareqv (double-rewrite a) (car y))
                        (icharlisteqv (double-rewrite x)
                                      (cdr y)))))

    Theorem: icharlisteqv-when-not-same-lens

    (defthm icharlisteqv-when-not-same-lens
            (implies (not (equal (len x) (len y)))
                     (not (icharlisteqv x y))))