lisp - how to return function in elisp -


this related question: elisp functions parameters , return value

(defun avg-damp (n)    '(lambda(x) (/ n 2.0)))

either

(funcall (avg-damp 6) 10)

or

((avg-damp 6) 10)

they gave errors of symbol's value variable void: n , eval: invalid function: (avg-damp 6) respectively.

the reason first form not work n bound dynamically, not lexically:

(defun avg-damp (n)   (lexical-let ((n n))     (lambda(x) (/ x n)))) (funcall (avg-damp 3) 12) ==> 4

the reason second form not work emacs lisp is, common lisp, a "lisp-2", not "lisp-1"


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