get lhs object name when piping with dplyr

Question

I\'d like to have a function that can use pipe operator as exported from dplyr. I am not using magrittr.

df %>% my_function

How can I get df

Answer 1

Here's a hacky way of doing it, which I'm sure breaks in a ton of edge cases:

library(data.table) # for the address function
                    # or parse .Internal(inspect if you feel masochistic

fn = function(tbl) {
  objs = ls(parent.env(environment()))
  objs[sapply(objs,
          function(x) address(get(x, env = parent.env(environment()))) == address(tbl))]
}

df = data.frame(a = 1:10)
df %>% fn
#[1] "df"