src/main/java/com/bazaarvoice/jless/parser/Parser.java
Rule Scope() {
        return Sequence(
                push(new ScopeNode()),
                ZeroOrMore(
                        FirstOf(
                                Declaration(),
                                MediaQuery(),
                                RuleSet(),
                                MixinReference(),
                                Sequence(push(new WhiteSpaceCollectionNode()), Sp1Nodes())
                        ),
                        peek(1).addChild(pop())
                )
        );
    }
Rule Scope() {
        return Sequence(
                push(new ScopeNode()),
                ZeroOrMore(
                        FirstOf(
                                Declaration(),
                                MediaQuery(),
                                RuleSet(),
                                MixinReference(),
                                Sequence(push(new WhiteSpaceCollectionNode()), Sp1Nodes())
                        ),
                        peek(1).addChild(pop())
                )
        );
    }
This is the high-level rule at some scope (either the root document or within a rule set / mixin).
Future: Imports