Required files
strscan
digest/sha1
sass/tree/node
sass/tree/rule_node
sass/tree/comment_node
sass/tree/prop_node
sass/tree/directive_node
sass/tree/variable_node
sass/tree/mixin_def_node
sass/tree/mixin_node
sass/tree/if_node
sass/tree/while_node
sass/tree/for_node
sass/tree/debug_node
sass/tree/import_node
sass/environment
sass/script
sass/error
sass/files
haml/shared