我在使用Dr Racket时遇到了读取输出的问题。默认情况下,它使用mcons显示列表。例如,SICP练习2.32会产生以下输出:
> (subsets (list 1 2 3))
(mcons
(mcons
'()
(mcons
(mcons 3 '())
(mcons
(mcons 2 '())
(mcons
(mcons 2 (mcons 3 '()))
(mcons
(mcons 1 '())
(mcons
(mcons 1 (mcons 3 '()))
(mcons
(mcons 1 (mcons 2 '()))
(mcons (mcons 1 (mcons 2 (mcons 3 '()))) '()))))))))
'())
我读起来有些困难。是否有一种方法可以使输出看起来像这样:
(() (3) (2) (2 3) (1) (1 3) (1 2) (1 2 3))
谢谢!