Is there a method to stop `lapply()` from returning NULL values for each element of the list when a function doesn't have a `return()`. 

Here's a pretty basic example: 

```
x <- function(x) {
return(NULL) }

a.list <- list(a=1,b=2,c=3)

lapply(a.list, x)

```

The output is:

```
$a
NULL

$b
NULL

$c
NULL

```

My goal is to not have that output, at all.

Update: my usage case is as follows. I'm using `lapply()` to pump out `xtable()` text and I'm `sink()`'ing it to an Rnw file. So this NULL output is bugging up my automation.