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| ANSI Common Lisp 5 Data and Control Flow 5.3 Dictionary of Data and Control Flow
5.3.39 constantly | Function
  Syntax: constantly value function Arguments and Values: value - an object. function - a function. Description: constantly returns a function that accepts any number of arguments, that has no side-effects, and that always returns value. Examples:
       (mapcar (constantly 3) '(a b c d))  (3 3 3 3)
       (defmacro with-vars (vars &body forms)
         `((lambda ,vars ,@forms) ,@(mapcar (constantly nil) vars)))
        WITH-VARS
       (macroexpand '(with-vars (a b) (setq a 3 b (* a a)) (list a b)))
       ((LAMBDA (A B) (SETQ A 3 B (* A A)) (LIST A B)) NIL NIL), true
  See Also: identity Notes: constantly could be defined by:
       (defun constantly (object)
         #'(lambda (&rest arguments) object))
Allegro CL Implementation Details: None.

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