Working with dictionaries/lists to get list of keys

hashmap, list, lookup, r

Solution

Yes, the `list` type is a good approximation. You can use `names()` on your list to set and retrieve the 'keys':

> foo <- vector(mode="list", length=3)
> names(foo) <- c("tic", "tac", "toe")
> foo[[1]] <- 12; foo[[2]] <- 22; foo[[3]] <- 33
> foo
$tic
[1] 12

$tac
[1] 22

$toe
[1] 33

> names(foo)
[1] "tic" "tac" "toe"
> 

Problem

I have trivial question: I couldn't find a dictionary data structure in R, so I used list instead (like `"word"->number`). So, how do I get the list of keys.

Original source