What you are looking for is purrr::pluck function
library(purrr)
test_list <- list(index = 1:3, data = letters[1:3])
test_list %>% pluck("index")
#> [1] 1 2 3
Created on 2018-09-12 by the reprex package (v0.2.0).
About pluck
This is a generalised form of [[ which allows you to index deeply and flexibly into data structures. It supports R standard accessors like integer positions and string names, and also accepts arbitrary accessor functions, i.e. functions that take an object and return some internal piece.
See the help page for more example. (it is hidden from the reference page listing, I don't know why...
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