map_df fails on character vector as .f when .x contains null

[yeedle]

Suppose I have a list with the following structure:

ls <- list(NULL, 
           list("foo"=data_frame(bar=c(1, 2, 3))), 
           list("foo"=data_frame(bar=c(4,5,6))))

using map_df to extract as a dataframe works well:

map_df(ls, ~.x[["foo"]])

## # A tibble: 6 × 1
##     bar
##   <dbl>
## 1     1
## 2     2
## 3     3
## 4     4
## 5     5
## 6     6

But if I pass in the name as an atomic character vector, I get an error:

map_df(ls, "foo")

## Error: `x` must be a vector (not a NULL)

[hadley]

This is fixed in the dev version. (And in the future, can you please use the reprex package to create reprexes)

[hadley]

(Not sure whether it's the dev version of purrr or dplyr, but it definitely works for me)

[yeedle]

Installed the dev version of purrr and it works for me too now. Thanks!