Re: [Rd] 'unique' error message is printed despite silent=TRUE (PR#13547)

From: Wacek Kusnierczyk <>
Date: Sun, 22 Feb 2009 22:38:01 +0100

Duncan Murdoch wrote:
>> hmm, why wouldn't you use something like
>> DEBUG(x)
>> with DEBUG being a macro defined so that it's replacement is void unless
>> a specific flag or environment variable is set specifically for the
>> purpose of debugging? you would then avoid confusing users' code just
>> because one PrintValue has been inadvertently left in the sources.
> But then we'd confuse developers, who would see a huge dump of messages
> from every other debugging session, when they just wanted to see their
> own, and who would be forced to wade through leftover never-used
> DEBUG(x) calls in code when they were reading the source.

my point was not that such DEBUG statements should be left there in the code for all eternity. to the contrary, their role would be quite the same as that of the PrintValue discussed here. it would, however, be easier to switch between printing and not printing such debugging messages, and also easier to spot DEBUG statements inadvertently left in the code.

> This is not a common error: as far as I know, there are no other
> unintentional PrintValue calls anywhere in the source. So I think the
> current system (just take them out before committing) is working.

grep --include=*.c -R '\bPrintValue\b' src | wc -l

reports 21 occurrences of PrintValue, though of course i cannot say anything about their being intentional or not unless i examine the sources. if they were DEBUGs, you'd know for sure they're not supposed to stay there in a release version.

it's just to wish that those who introduce debugging PrintValues examined diffs carefully before their code is released. given the size of r sources (and their fairly ad hoc shape here and there), few others than the author will know for sure whether the PrintValue is a debugger or not? apparently, no one has noticed in this case. were it DEBUG instead of PrintValue, it would suffice to run a grep to catch it.

vQ mailing list Received on Sun 22 Feb 2009 - 20:39:54 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Sun 22 Feb 2009 - 22:30:32 GMT.

Mailing list information is available at Please read the posting guide before posting to the list.

list of date sections of archive