How to call an element of an object created with a magrittr pipe?

Using the magrittr piper operator we perform manipulation on a vector.

strings <- "a b c"
strings %>% strsplit(" ") # Here we get a list 


> strings %>% strsplit(" ")
[[1]]
[1] "a" "b" "c"

But let's assume that we would only like to get the single element of this list. This would require us to (example to get the first element):

(strings %>% strsplit(" "))[[1]][1] # Notice the braces around the expression..

Now to my question: Is there a way to use the pipe operator without the need of putting the whole expression in braces? It would be more transparent, I think, if we would not have to write it into a temporary variable or use brackets but use some kind of a special pipe operator.

Is there another way to do this?

Solution

Or also:

strings %>% strsplit(" ") %>% { .[[1]][1] }

which would be the same as

strings %>% strsplit(" ") %>% .[[1]] %>% .[1]

Compare the timings:

library(purrr)
library(dplyr)
microbenchmark::microbenchmark(
  (strings %>% strsplit(" ") %>%  unlist %>%  first)
  ,(strings %>%  strsplit(" ") %>% { .[[1]][1] })
  ,(strings %>% strsplit(" ") %>% map_chr(1))
)
# Unit: microseconds
#                                          expr     min      lq       mean     median       uq      max    neval
# (strings %>% strsplit(" ") %>% unlist %>% first)   280.270 288.363  301.9581 295.4685 305.1395  442.511   100
# (strings %>% strsplit(" ") %>% {     .[[1]][1] })  211.980 219.875  229.4866 226.3875 235.6640  298.429   100
# (strings %>% strsplit(" ") %>% map_chr(1))         682.123 693.965 747.1690 710.1495 752.3875  2578.091   100