# NOT RUN {
# The `abort` restart is a bit special in that it is always
# registered in a R session. You will always find it on the restart
# stack because it is established at top level:
rst_list()
# You can use the `above` restart to jump to top level without
# signalling an error:
# }
# NOT RUN {
fn <- function() {
cat("aborting...\n")
rst_abort()
cat("This is never called\n")
}
{
fn()
cat("This is never called\n")
}
# }
# NOT RUN {
# The `above` restart is the target that R uses to jump to top
# level when critical errors are signalled:
# }
# NOT RUN {
{
abort("error")
cat("This is never called\n")
}
# }
# NOT RUN {
# If another `abort` restart is specified, errors are signalled as
# usual but then control flow resumes with from the new restart:
# }
# NOT RUN {
out <- NULL
{
out <- with_restarts(abort("error"), abort = function() "restart!")
cat("This is called\n")
}
cat("`out` has now become:", out, "\n")
# }
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