capturing warnings using capture.output

options(warn=0)
txt0 <- capture.output({message("A message"); warning("A warning")}, type="message")

options(warn=1)
txt1 <- capture.output({message("A message"); warning("A warning")}, type="message")
txt0

txt1

From the Details section of ?capture.output:

Messages sent to stderr() (including those from message, warning and stop)
are captured by type = "message". Note that this can be "unsafe" and should
only be used with care.

Capturing messages works as expected:

capture.output(message("!!!"), type = "message")
## [1] "!!!"

Capturing warnings doesn't seems to work:

capture.output(warning("!!!"), type = "message")
## character(0)
## Warning message:
## In eval(expr, envir, enclos) : !!!

Is the documentation wrong, or is this a bug, or am I doing doing silly?

--
Regards,
Richie

Learning R
4dpiecharts.com

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