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    =

    Test equality of two numbers

    (= x y) is logically equivalent to (equal x y).

    Unlike equal, = has a guard requiring both of its arguments to be numbers. Generally, = is executed more efficiently than equal.

    For a discussion of the various ways to test against 0, See zero-test-idioms.

    = is a Common Lisp function. See any Common Lisp documentation for more information.

    Function: =

    (defun = (x y)
      (declare (xargs :guard (and (acl2-numberp x)
                                  (acl2-numberp y))))
      (equal x y))