R syntax highlighting for nano editor

R.nanorc

################################################################################
#
# R.nanorc -- nano syntax-highlighting file for R
#
# Origin: This file is part of the pkgutils package for R.
#
# Usage: This file should be placed in a directory such as /usr/share/nano/ (on
#   Ubuntu 12.04). That nano uses syntax highlighting at all might need to be
#   enabled separately.
#
# Limitations: The syntax is covered as completely as possible; for instance,
#   all reserved words are marked in a uniform way. That R syntactical names
#   may contain dots, however, appears to make it impossible to hightlight
#   them properly using nano's limited regular-expression capabilities.
#
# NB: This syntax highlighting distinguishes between normal and Roxygen-style
#   comments.
#
# (C) 2012 by Markus Goeker (markus [DOT] goeker [AT] dsmz [DOT] de)
#
# This program is distributed under the terms of the Gnu Public License V2.
#   For further information, see http://www.gnu.org/licenses/gpl.html
#
################################################################################


##
syntax "R" "\.R$"
header "^#!.*/Rscript"

## Asciibetical list of reserved words, including '...', '..1' etc.
color brightgreen "(\<(break|else|for|function|if|in|next|repeat|return|while)\>|[.]{3,3}|[.]{2,2}[0-9]+)"

## Assignment operators (only the preferred '<-' and '<<-' ones)
color green "(<){1,2}-"

## Delimiters 
color green "[\)\(,;]+|[\{\}]+|[][]+"

## Boolean
color brightblue "\<(TRUE|FALSE|NA)\>"

## Other special constants
color brightblue "\<(Inf|NA_character_|NA_complex_|NA_integer_|NA_real_|NaN|NULL)\>"

## Special operators (infix operators)
color brightcyan "%[^%]*%"

## Integers
color brightred "(\b|-)[0-9]+[iL]?\b"

## Floating-point numbers
color brightred "(\b|-)([0-9]+[Ee][-+]?[0-9]+|([0-9]*\.[0-9]+|[0-9]+\.)([Ee][-+]?[0-9]+)?)[i]?\b"

## Backtic-quoted names
color brightmagenta "`[^`]*`"

## Unevaluated words (as occurring in '$' and '@' operators)
color brightwhite "[@$][a-zA-Z.][a-zA-Z0-9._]*"

## Strings, double-quoted
color brightyellow ""([^"]|(\\"))*""

## Strings, single-quoted
color brightyellow "'([^']|(\\'))*'"

## Comments
color magenta "#[^'].*$" "#$"

## Special comments (Roxygen-style)
color cyan "#'.*$"

Hi. I'm commenting this to remember. Add this code here:

~/.nano/syntax/R.nanorc
Then add this line in .nanorc

nano ~/.nanorc
include ~/.nano/syntax/R.nanorc

Thanks!

Change:
syntax "R" "\.R$"

To:
syntax "R" "\.[Rr]$"

To highlight files with a lowercase 'r' extension.