scheme - 列出方案中所有用户定义的变量

Question

在 python 中，我可以使用 dir()在 Racket (5.2)中我可以做到

 (require xrepl)
 ,apropos

获取所有已定义变量的列表。在所有方案中都有什么可移植的方法来做同样的事情？完成后，如何过滤掉所有系统和模块变量？变量的完整列表在 Racket 中相当令人生畏。

Answer 1

要获取 Racket 中特定模块导出的名称，请使用 module->exports .对于其他实现，您需要在文档中查找。

> (module->exports 'racket/list)
'((0
   (add-between ()) (append* ())    (append-map ())
   (argmax ())      (argmin ())     (cons? ()) (count ())
   (drop ())        (drop-right ()) (eighth ()) (empty ())
   (empty? ())      (fifth ())      (filter-map ())
   (filter-not ())  (first ())      (flatten ())
   (fourth ())      (last ())       (last-pair ())
   (make-list ())   (ninth ())      (partition ())
   (range ())       (rest ())       (second ())
   (seventh ())     (shuffle ())    (sixth ())
   (split-at ())    (split-at-right ()) (take ())
   (take-right ())  (tenth ()) (third ())))
'((0 (remove-duplicates ())))