assertive和assertthat具有更易读的检查功能。

library(assertthat)
assert_that(length(unique(nchar(check))) == 1)
## Error: length(unique(nchar(check))) == 1 are not all true.

library(assertive)
assert_is_scalar(unique(nchar(check)))
## Error: unique(nchar(check)) does not have length one.

if(!is_scalar(unique(nchar(check)))) 
{
  stop("Elements of check have different numbers of characters.")
}
## Error: Elements of check have different numbers of characters.