[Rd] OT: Reason/history behind ## notation for comments?

[Henrik Bengtsson]

Off topic, but since I've observe both styles, does anyone know the
history behind/reason for using ## instead of a single # to start
comments in R.  I know some editors do this by default.  Is it because
in C it is easier to distinguish (search/replace/...) comments from C
preprocessor directives such as #include, and that's became a de facto
standard elsewhere?

/Henrik

PS. I don't want to get into a debate on what's the best style.