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    String-equal

    String equality without regard to case

    For strings str1 and str2, (string-equal str1 str2) is true if and only str1 and str2 are the same except perhaps for the cases of their characters.

    The guard on string-equal requires that its arguments are strings.

    String-equal is a Common Lisp function. See any Common Lisp documentation for more information. Note that the value returned may depend on the host Lisp; see soundness, specifically Example 1 in the Section, “Examples of divergence among Lisp implementations”.

    Function: string-equal

    (defun string-equal (str1 str2)
      (declare (xargs :guard (and (stringp str1) (stringp str2))))
      (let ((len1 (length str1)))
        (and (= len1 (length str2))
             (string-equal1 str1 str2 0 len1))))