[Rd] calls with comment attribute

Tomas Kalibera tom@@@k@||ber@ @end|ng |rom gm@||@com
Thu Nov 28 23:18:07 CET 2019

Thanks for spotting this, I've removed the old code in deparse so that 
now the comment attribute is really not printed, as documented in 
?comment. The removed code was needed at the time when comments were 
collected by the parser and stored in the comment attribute, but that is 
no longer the case, now comments are part of source references.


On 11/13/19 4:15 AM, William Dunlap via R-devel wrote:
> I suspect that the parser used it to store comments, including the initial
> "#", before R started using the srcref attribute.  (S also stored comments
> in the parse tree.)
> Bill Dunlap
> TIBCO Software
> wdunlap tibco.com
> On Tue, Nov 12, 2019 at 4:16 PM Duncan Murdoch <murdoch.duncan using gmail.com>
> wrote:
>> On 12/11/2019 5:01 p.m., William Dunlap via R-devel wrote:
>>> In general R doesn't print the "comment" attribute of an object
>>>      > structure(1:3, comment=c("a comment", "another comment"))
>>>      [1] 1 2 3
>>> but if the object is a call it prints it in an unusual format
>>>      > structure(quote(func(arg)), comment=c("a comment", "another
>> comment"))
>>>      a comment
>>>      another comment
>>>      func(arg)
>>> What is the rationale for the special treatment of calls?
>> It was there in revision 2 of src/main/deparse.c in 1997.  (For those
>> unfamiliar with R history:  the current revision of R is 77405.  That
>> particular file has been revised 248 times since rev 2.)
>> I suspect either nobody has noticed it before, or nobody had the nerve
>> to touch it.
>> Duncan Murdoch
> 	[[alternative HTML version deleted]]
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