Q4 in 8.4.5. catch_cnd source changed

[FGL-Linear]

Citing Advanced R solutions:

At the time Advanced R was written, the source for catch_cnd() was a little simpler

catch_cnd <- function(expr) {
  tryCatch(
    condition = function(cnd) cnd,
    {
      force(expr)
      return(NULL)
    }
  )
}

Maybe it would be a good idea to include the old source to the question.