Use .data in pack()

[yusuzech]

In dplyr functions, the first argument are mostly .data to prevent possible conflicts. But in tidyr, most functions use data as the first argument. And it creates an issue that when setting data as column name.

For example:

Since data is already used as the first argument of pack() function, when using "data" as a column, it will throw an error message.

df <- tibble(x1 = 1:3, x2 = 4:6, x3 = 7:9, y = 1:3)
df %>% pack(data = c(x1, x2, x3), y = y) 

throws an error message:

Error: All elements of `...` must be named

The same applies to at least pack, unpack, chop and unchop

[hadley]

I think this only applies to pack() and unnest(), because chop(), unchop(), and unpack() don't have ....

[hadley]

And ... is deprecated in unnest(), so pack() is the only function that needs a fix.