— procedure: apply procedure object object ...

Calls procedure with the elements of the following list as arguments:

          (cons* object object ...)
     

The initial objects may be any objects, but the last object (there must be at least one object) must be a list.

          (apply + (list 3 4 5 6))                =>  18
          (apply + 3 4 '(5 6))                    =>  18
          
          (define compose
            (lambda (f g)
              (lambda args
                (f (apply g args)))))
          ((compose sqrt *) 12 75)                =>  30
     

— procedure: procedure? object

Returns #t if object is a procedure; otherwise returns #f. If #t is returned, exactly one of the following predicates is satisfied by object: compiled-procedure?, compound-procedure?, or primitive-procedure?.

— procedure: compiled-procedure? object

Returns #t if object is a compiled procedure; otherwise returns #f.

— procedure: compound-procedure? object

Returns #t if object is a compound (i.e. interpreted) procedure; otherwise returns #f.

— procedure: primitive-procedure? object

Returns #t if object is a primitive procedure; otherwise returns #f.

— procedure: procedure-environment procedure

Returns the closing environment of procedure. Signals an error if procedure is a primitive procedure, or if procedure is a compiled procedure for which the debugging information is unavailable.