foo.scss

$variable: #ffffff;

body {
        background-color: $variable;
}       

Nanoc output

$ nanoc compile
Loading site data...
Compiling site...
   identical  [2.20s]  _site/index.html

+--- /!\ ERROR /!\ -------------------------------------------+
| An exception occured while running nanoc. If you think this |
| is a bug in nanoc, please do report it at                   |
| <http://projects.stoneship.org/trac/nanoc/newticket> --     |
| thanks in advance!                                          |
+-------------------------------------------------------------+

=== MESSAGE:

Sass::SyntaxError: Invalid CSS after "#ffffff": expected expression (e.g. 1px, bold), was ";"

=== COMPILATION STACK:

  - [item]   /css/foo/ (rep default)

=== BACKTRACE:

  0. content/css/foo.scss:1
  1. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/scss/parser.rb:838:in `expected'
  2. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/script/lexer.rb:193:in `expected!'
  3. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/script/parser.rb:392:in `assert_done'
  4. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/script/parser.rb:50:in `parse'
  5. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/script/parser.rb:120:in `parse'
  6. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/script.rb:32:in `parse'
  7. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:672:in `parse_script'
  8. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:491:in `parse_variable'
  9. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:424:in `parse_line'
  10. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:328:in `build_tree'
  11. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:347:in `block in append_children'
  12. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:346:in `each'
  13. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:346:in `append_children'
  14. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:216:in `_to_tree'
  15. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/haml-3.0.25/lib/sass/engine.rb:178:in `to_tree'
  16. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/filters/sass.rb:33:in `run'
  17. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/base/item_rep.rb:279:in `filter'
  18. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/base/rule_context.rb:51:in `filter'
  19. ./Rules:15:in `block in load_rules'
  20. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/base/rule.rb:51:in `instance_eval'
  21. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/base/rule.rb:51:in `apply_to'
  22. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/base/compiler.rb:219:in `compile_rep'
  23. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/base/compiler.rb:155:in `compile_reps'
  24. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/base/compiler.rb:82:in `run'
  25. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/cli/commands/compile.rb:84:in `run'
  26. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/cri-1.0.1/lib/cri/base.rb:91:in `run'
  27. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/lib/nanoc3/cli/base.rb:76:in `run'
  28. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/gems/nanoc3-3.1.6/bin/nanoc3:12:in `<top (required)>'
  29. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/bin/nanoc3:19:in `load'
  30. /home/ilkka/.rvm/gems/ruby-1.9.2-p0@nanoc/bin/nanoc3:19:in `<main>'

Rules.rb

#!/usr/bin/env ruby

# A few helpful tips about the Rules file:
#
# * The order of rules is important: for each item, only the first matching
#   rule is applied.
#
# * Item identifiers start and end with a slash (e.g. "/about/" for the file
#   "content/about.html"). To select all children, grandchildren, ... of an
#   item, use the pattern "/about/*/"; "/about/*" will also select the parent,
#   because "*" matches zero or more characters.
  
# do stylesheets with sass
compile '/css/*/' do
  filter :sass
end
  
# route stylesheets
route '/css/*/' do
  item.identifier.gsub(/\.scss$/, ".css")
end
  
# catchall: default layout and filter
compile '*' do
  filter :kramdown
  layout 'default'
end

# default route
route '*' do
  item.identifier + 'index.html'
end 
  
# process all layouts with HAML
layout '*', :haml