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| ANSI Common Lisp 5 Data and Control Flow 5.3 Dictionary of Data and Control Flow
5.3.56 nth-value | Macro
  Syntax: nth-value n form object Arguments and Values: n - a non-negative integer; evaluated. form - a form; evaluated as described below. object - an object. Description: Evaluates n and then form, returning as its only value the nth value yielded by form, or nil if n is greater than or equal to the number of values returned by form. (The first returned value is numbered `0`.) Examples:
       (nth-value 0 (values 'a 'b))   A
       (nth-value 1 (values 'a 'b))   B
       (nth-value 2 (values 'a 'b))   NIL
       (let* ((x 83927472397238947423879243432432432)
              (y 32423489732)
              (a (nth-value 1 (floor x y)))
              (b (mod x y)))
         (values a b (= a b)))
       3332987528, 3332987528, true
  See Also: multiple-value-list, nth Notes: Operationally, the following relationship is true, although nth-value might be more efficient in some implementations because, for example, some consing might be avoided.
       (nth-value n form) ==(nth n (multiple-value-list form))
Allegro CL Implementation Details: None.

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