pipe_return

Added in 0.6.0

What it does

Reports return() used on the right-hand side of the magrittr pipe %>%, whether written with parentheses (x %>% return()) or as a bare identifier (x %>% return).

The native pipe |> is not considered because x |> return() is a syntax error and would be caught by the parser anyway.

Why is this bad?

return() on the right-hand side of %>% does not behave like a regular return() call and doesn’t exit the function early. See the examples below.

Example

f <- function(x) {
  x %>% sum() %>% return()
  1 + 1
}

f(1:3)
#> 2

In the example above, the output isn’t the sum of x but 1 + 1, even though we’d expect the return() to return the output of x %>% sum().

Wrapping the pipe in return() instead is unambiguous:

f <- function(x) {
  return(x %>% sum())
  1 + 1
}

# OR:
f <- function(x) {
  out <- x %>% sum()
  return(out)
  1 + 1
}

f(1:3)
#> 6