r - 映射列表，获取项目名称和内容

Question

my_dfs <- list(
  mtcars = mtcars,
  diamonds = diamonds
)
map(.x = my_dfs, ~ print(.x %>% str)) # OK

但是如果我还想访问正在打印的列表中的项目的名称，我该怎么做呢？

map(.x = my_dfs, ~ print(.id)) # found a reference to .id in the docs.
Error in print(.id) : object '.id' not found

更好的是，我希望同时调用 map，例如

map(.x = my_dfs, ~ print('About to print str of ' [somehow get list item name here] .x %>% str))

Answer 1

使用imap()。内容将由 .x 引用，名称由 .y 引用。

z <- list(x = "whats in x",
          y = "whats in y")

imap(z, ~ paste(.y, "has contents:", .x))
# $x
# [1] "x has contents: whats in x"
# 
# $y
# [1] "y has contents: whats in y"