如果您知道要从哪个级别提取信息，您可以使用 modify_depth 来解决这个问题.

You can use modify_depth for this if you know what level you want to pull the information out of.

您想为嵌套列表提取 t，这是级别 2.

You want to pull t out for the nested lists, which is level 2.

modify_depth(list, 2, "t")

$node
$node$a
[1] 1

$node$b
[1] 2


$node
$node$a
[1] 3

$node$b
[1] 4

purrr modify 函数系列返回与输入类型相同的对象，因此您需要 unlist 以获取一个向量而不是一个列表.

The purrr modify family of functions returns an object of the same type as the input, so you'd need to unlist to get a vector instead of a list.