我正在尝试在OCaml中实现一个尾递归的列表排序函数,我已经想出了以下代码:
let tailrec_merge_sort l =
let split l =
let rec _split source left right =
match source with
| [] -> (left, right)
| head :: tail -> _split tail right (head :: left)
in _split l [] []
in
let merge l1 l2 =
let rec _merge l1 l2 result =
match l1, l2 with
| [], [] -> result
| [], h :: t | h :: t, [] -> _merge [] t (h :: result)
| h1 :: t1, h2 :: t2 ->
if h1 < h2 then _merge t1 l2 (h1 :: result)
else _merge l1 t2 (h2 :: result)
in List.rev (_merge l1 l2 [])
in
let rec sort = function
| [] -> []
| [a] -> [a]
| list -> let left, right = split list in merge (sort left) (sort right)
in sort l
;;
然而,似乎它并不是尾递归,因为我遇到了“在评估过程中出现堆栈溢出(循环递归?)”的错误。
请帮我找出这段代码中的非尾递归调用。我已经搜索了很多次,但没有找到。可能是sort
函数中的let绑定吗?