entrace()
is a low level function. See global_entrace()
for a
user-friendly way of enriching errors and other conditions from
your RProfile.
entrace()
is meant to be used as a global handler. It enriches
conditions with a backtrace. Errors are saved to last_error()
and rethrown immediately. Messages and warnings are recorded into
last_messages()
and last_warnings()
and let through.
cnd_entrace()
adds a backtrace to a condition object, without
any other effect. It should be called from a condition handler.
entrace()
also works as an option(error = )
handler for
compatibility with versions of R older than 4.0.
When used as calling handler, rlang trims the handler invokation context from the backtrace.
entrace(cnd, ..., top = NULL, bottom = NULL)
cnd_entrace(cnd, ..., top = NULL, bottom = NULL)
When entrace()
is used as a calling handler, cnd
is
the condition to handle.
Unused. These dots are for future extensions.
The first frame environment to be included in the backtrace. This becomes the top of the backtrace tree and represents the oldest call in the backtrace.
This is needed in particular when you call trace_back()
indirectly or from a larger context, for example in tests or
inside an RMarkdown document where you don't want all of the
knitr evaluation mechanisms to appear in the backtrace.
If not supplied, the rlang_trace_top_env
global option is
consulted. This makes it possible to trim the embedding context
for all backtraces created while the option is set. If knitr is
in progress, the default value for this option is
knitr::knit_global()
so that the knitr context is trimmed out
of backtraces.
The last frame environment to be included in the backtrace. This becomes the rightmost leaf of the backtrace tree and represents the youngest call in the backtrace.
Set this when you would like to capture a backtrace without the capture context.
Can also be an integer that will be passed to caller_env()
.
global_entrace()
for configuring errors with
entrace()
. cnd_entrace()
to manually add a backtrace to a
condition.
quote({ # Not run
# Set `entrace()` globally in your RProfile
globalCallingHandlers(error = rlang::entrace)
# On older R versions which don't feature `globalCallingHandlers`,
# set the error handler like this:
options(error = rlang::entrace)
})
#> {
#> globalCallingHandlers(error = rlang::entrace)
#> options(error = rlang::entrace)
#> }