通过数字列表过滤 [英] Filtering through a list of numbers

问题描述

这是我的咖喱函数:

(define (curry g)
  (lambda(x)
    (lambda(y)
      (g x y))))

我正在尝试使用 curry 函数生成一个不等于 1 的数字列表.

I'm trying to produce a list of numbers not equal to 1 using the curry function.

到目前为止我所拥有的是:

What I have so far is:

(define filter-numbers ((curry filter)
                       ((curry equal?) 1)))

但它只生成等于 1 的数字列表.

But it only produces the list of numbers equal to 1.

例如.(filter-numbers (list 1 2 3)) -> (list 1)

ex. (filter-numbers (list 1 2 3)) -> (list 1)

我想获得(列表 2 3)但不知道如何获得.有人可以帮忙吗?

I want to get (list 2 3) but have no idea how. Can anyone help?

推荐答案

试试这个 - 这是 Racket 中的正确方法，使用内置的 curry 和 href="http://docs.racket-lang.org/reference/pairs.html#%28def._%28%28lib._racket%2Flist..rkt%29._filter-not%29%29" rel="nofollow">filter-not 程序:

Try this - is the right approach in Racket, using the built-in curry and filter-not procedures:

(define filter-numbers 
  (curry filter-not (curry equal? 1)))

或者，使用您的 curry 实现:

Alternatively, using your implementation of curry:

(define filter-numbers 
  ((curry filter-not)
   ((curry equal?) 1)))

无论哪种方式，它都按预期工作:

Either way, it works as expected:

(filter-numbers '(1 2 3 4 5 1 7 1))
=> '(2 3 4 5 7)

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