[R] How to comment in R

Wacek Kusnierczyk Waclaw.Marcin.Kusnierczyk at idi.ntnu.no
Wed Feb 11 20:25:58 CET 2009

Stavros Macrakis wrote:
> On Wed, Feb 11, 2009 at 12:32 PM, Greg Snow <Greg.Snow at imail.org> wrote:
>> ...The c-style of /* */ allows both types and you can comment out part of a line, but it is not simple to match and has its own restrictions.  Friedl in his regular expressions book takes 10 pages to develop a pattern to match these (and the final pattern is almost 2 full lines of text in the book).  And this is without allowing nesting....
> Though there is a real debate about the value of multiline, possibly
> nested, comments, the regular expression argument is a red herring.
> Lexical analysis of multiline comments is a solved problem (and not a
> particularly difficult one!), and matters only to language and editor
> implementors.  Emacs handles them with no problem.

indeed.  but any argument is good to defend whatever has been or hasn't
been implemented in r.

> PS And to give credit where credit is due (important on this mailing
> list), the /* */ syntax was defined by PL/I; C simply implemented an
> existing convention and popularized it. :-)

it might be my fault, i was talking about c-style comments here, not
sure if i was the first to do so.


Wacek Kusnierczyk, MD PhD

Email: waku at idi.ntnu.no
Phone: +47 73591875, +47 72574609

Department of Computer and Information Science (IDI)
Faculty of Information Technology, Mathematics and Electrical Engineering (IME)
Norwegian University of Science and Technology (NTNU)
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Room itv303

Bioinformatics & Gene Regulation Group
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