[R] How to comment in R

Stavros Macrakis macrakis at alum.mit.edu
Wed Feb 11 19:21:41 CET 2009

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.


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. :-)

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