Efficient way of creating a data frame from columns

[hadley]

i.e. so instead of

x <- runif(10)
data.frame(x = x, y = x * 2)

you could do

data_frame(x = runif(10), y = x * 2)

Would support standard dplyr features:

• errors for non-supported vector types
• only recycle vectors of length 1
• one versions for ... input, one version of list input
• fast!

[romainfrancois]

That should be fun. I guess some of the tools of mutate can be reused for that.

[hadley]

I'd really like to include this in the next version.

[hadley]

Two other notes:

• it should always return an object of class tbl_df, data.frame
• it should do minimal transformation on its inputs so that data.frame(list(1, 2, 3)) works (needs to check that vectors are all of same length, and matrices/arrays have first dim of correct length)

[hadley]

Done in cda0232