This is a small wrapper around tryCatch() that captures any
condition signalled while evaluating its argument. It is useful for
situations where you expect a specific condition to be signalled,
for debugging, and for unit testing.
catch_cnd(expr, classes = "condition")
| expr | Expression to be evaluated with a catching condition handler. |
|---|---|
| classes | A character vector of condition classes to catch. By default, catches all conditions. |
A condition if any was signalled, NULL otherwise.
catch_cnd(10)#> NULL#> <error> #> message: an error #> class: `rlang_error` #> backtrace: #> 1. base::tryCatch(...) #> 13. pkgdown::build_site(...) #> 14. pkgdown:::build_site_local(...) #> 15. pkgdown::build_reference(...) #> 16. purrr::map(...) #> 17. pkgdown:::.f(.x[[i]], ...) #> 18. pkgdown:::data_reference_topic(...) #> 20. pkgdown:::as_data.tag_examples(...) #> 21. purrr::pmap_chr(...) #> 22. pkgdown:::.f(...) #> 25. evaluate::evaluate(code, env, new_device = TRUE) #> 26. evaluate:::evaluate_call(...) #> 36. [ base::eval(...) ] with 1 more call #> 38. rlang::catch_cnd(abort("an error")) #> 44. base::force(expr) /home/travis/build/r-lib/rlang/R/cnd.R:579:6 #> Call `rlang::last_trace()` to see the full backtrace#> <simpleError in cnd_signal("my_condition", .msg = "a condition"): unused argument (.msg = "a condition")>