[Rd] Environmental Messaging

[Koenker, Roger W]

What sort of message is this to send to the younger generation?

> plastic = 1:5
> card = 1:4
> board = 1:4
> plastic/crossprod(card,board)
[1] 0.03333333 0.06666667 0.10000000 0.13333333 0.16666667
Warning message:
In plastic/crossprod(card, board) :
  Recycling array of length 1 in vector-array arithmetic is deprecated.
  Use c() or as.vector() instead.

ok,  I can write c(crossprod()) but it is ugly, and environmentally wasteful.
What’s next?  Warnings for my beloved  outer(card, board) * board