R doesn’t come with a built-in constructor function for conditions, but we can easily add one.
(Advanced R, by Hadley Wickham)
Actually, there is simpleCondition(), simpleError() and the like, but they don't allow specifying an additional class. The functions in this package allow it:
library(condition)
cond <- new_error("Something went wrong", class = "oops")
cond## <oops: Something went wrong>
is.error(cond)## [1] TRUE
See the vignette for additional details.