diff --git a/.clang-format b/.clang-format
index 8d2eba22..633dfd06 100644
--- a/.clang-format
+++ b/.clang-format
@@ -9,7 +9,7 @@ AlignTrailingComments: true
 AllowAllParametersOfDeclarationOnNextLine: true
 AllowShortBlocksOnASingleLine: false
 AllowShortCaseLabelsOnASingleLine: false
-AllowShortFunctionsOnASingleLine: All
+AllowShortFunctionsOnASingleLine: Empty
 AllowShortIfStatementsOnASingleLine: false
 AllowShortLoopsOnASingleLine: false
 AlwaysBreakAfterDefinitionReturnType: None
diff --git a/src/compiler/build_tables/get_metadata.cc b/src/compiler/build_tables/get_metadata.cc
index da49d103..5c051e0e 100644
--- a/src/compiler/build_tables/get_metadata.cc
+++ b/src/compiler/build_tables/get_metadata.cc
@@ -21,7 +21,9 @@ int get_metadata(const rules::rule_ptr &rule, rules::MetadataKey key) {
     // TODO -
     // Remove this. It is currently needed to make the rule generated
     // by `LexTableBuilder::after_separators` have the right precedence.
-    int apply_to(const rules::Seq *rule) { return apply(rule->left); }
+    int apply_to(const rules::Seq *rule) {
+      return apply(rule->left);
+    }
   };
 
   return GetMetadata(key).apply(rule);
diff --git a/src/compiler/build_tables/item.cc b/src/compiler/build_tables/item.cc
index 85d2f2eb..155d19b7 100644
--- a/src/compiler/build_tables/item.cc
+++ b/src/compiler/build_tables/item.cc
@@ -10,9 +10,13 @@ namespace build_tables {
 Item::Item(const rules::Symbol &lhs, const rules::rule_ptr rule)
     : lhs(lhs), rule(rule) {}
 
-bool Item::is_done() const { return rule_can_be_blank(rule); }
+bool Item::is_done() const {
+  return rule_can_be_blank(rule);
+}
 
-int Item::precedence() const { return get_metadata(rule, rules::PRECEDENCE); }
+int Item::precedence() const {
+  return get_metadata(rule, rules::PRECEDENCE);
+}
 
 }  // namespace build_tables
 }  // namespace tree_sitter
diff --git a/src/compiler/build_tables/rule_can_be_blank.cc b/src/compiler/build_tables/rule_can_be_blank.cc
index 687bbeb6..88a3460d 100644
--- a/src/compiler/build_tables/rule_can_be_blank.cc
+++ b/src/compiler/build_tables/rule_can_be_blank.cc
@@ -16,9 +16,13 @@ using std::set;
 
 class CanBeBlank : public rules::RuleFn<bool> {
  protected:
-  bool apply_to(const rules::Blank *) { return true; }
+  bool apply_to(const rules::Blank *) {
+    return true;
+  }
 
-  bool apply_to(const rules::Repeat *rule) { return true; }
+  bool apply_to(const rules::Repeat *rule) {
+    return true;
+  }
 
   bool apply_to(const rules::Choice *rule) {
     for (const auto &element : rule->elements)
@@ -31,7 +35,9 @@ class CanBeBlank : public rules::RuleFn<bool> {
     return apply(rule->left) && apply(rule->right);
   }
 
-  bool apply_to(const rules::Metadata *rule) { return apply(rule->rule); }
+  bool apply_to(const rules::Metadata *rule) {
+    return apply(rule->rule);
+  }
 };
 
 class CanBeBlankRecursive : public CanBeBlank {
diff --git a/src/compiler/generate_code/c_code.cc b/src/compiler/generate_code/c_code.cc
index 639c9304..50204c25 100644
--- a/src/compiler/generate_code/c_code.cc
+++ b/src/compiler/generate_code/c_code.cc
@@ -315,7 +315,9 @@ class CCodeGenerator {
 
   // Helper functions
 
-  string lex_state_index(size_t i) { return to_string(i + 1); }
+  string lex_state_index(size_t i) {
+    return to_string(i + 1);
+  }
 
   string symbol_id(const rules::Symbol &symbol) {
     if (symbol.is_built_in()) {
@@ -429,7 +431,9 @@ class CCodeGenerator {
 
   // General code generation functions
 
-  void line() { line(""); }
+  void line() {
+    line("");
+  }
 
   void line(string input) {
     add("\n");
@@ -450,7 +454,9 @@ class CCodeGenerator {
     indent_level--;
   }
 
-  void add(string input) { buffer += input; }
+  void add(string input) {
+    buffer += input;
+  }
 };
 
 string c_code(string name, const ParseTable &parse_table,
diff --git a/src/compiler/grammar.cc b/src/compiler/grammar.cc
index 0376d77d..9cd1a555 100644
--- a/src/compiler/grammar.cc
+++ b/src/compiler/grammar.cc
@@ -29,7 +29,9 @@ bool Grammar::operator==(const Grammar &other) const {
   return true;
 }
 
-string Grammar::start_rule_name() const { return rules_.front().first; }
+string Grammar::start_rule_name() const {
+  return rules_.front().first;
+}
 
 ostream &operator<<(ostream &stream, const Grammar &grammar) {
   stream << string("#<grammar");
@@ -78,6 +80,8 @@ Grammar &Grammar::expected_conflicts(const set<set<string>> &expected_conflicts)
   return *this;
 }
 
-const vector<pair<string, rule_ptr>> &Grammar::rules() const { return rules_; }
+const vector<pair<string, rule_ptr>> &Grammar::rules() const {
+  return rules_;
+}
 
 }  // namespace tree_sitter
diff --git a/src/compiler/parse_table.cc b/src/compiler/parse_table.cc
index 9e3372e9..9970be46 100644
--- a/src/compiler/parse_table.cc
+++ b/src/compiler/parse_table.cc
@@ -29,7 +29,9 @@ ParseAction::ParseAction()
       consumed_symbol_count(0),
       associativity(rules::AssociativityUnspecified) {}
 
-ParseAction ParseAction::Error() { return ParseAction(); }
+ParseAction ParseAction::Error() {
+  return ParseAction();
+}
 
 ParseAction ParseAction::Accept() {
   ParseAction action;
diff --git a/src/compiler/prepare_grammar/extract_tokens.cc b/src/compiler/prepare_grammar/extract_tokens.cc
index 28a91cc8..ef94ea96 100644
--- a/src/compiler/prepare_grammar/extract_tokens.cc
+++ b/src/compiler/prepare_grammar/extract_tokens.cc
@@ -43,7 +43,9 @@ class SymbolReplacer : public rules::IdentityRuleFn {
     return result;
   }
 
-  rule_ptr apply_to(const Symbol *rule) { return replace_symbol(*rule).copy(); }
+  rule_ptr apply_to(const Symbol *rule) {
+    return replace_symbol(*rule).copy();
+  }
 
  public:
   map<Symbol, Symbol> replacements;
@@ -98,7 +100,6 @@ static const GrammarError *ubiq_token_err(const string &msg) {
                           "Not a token: " + msg);
 }
 
-
 tuple<SyntaxGrammar, LexicalGrammar, const GrammarError *> extract_tokens(
   const InternedGrammar &grammar) {
   SyntaxGrammar syntax_grammar;
@@ -108,14 +109,16 @@ tuple<SyntaxGrammar, LexicalGrammar, const GrammarError *> extract_tokens(
 
   vector<pair<string, rule_ptr>> extracted_rules;
   for (auto &pair : grammar.rules)
-    extracted_rules.push_back({pair.first, extractor.apply(pair.second)});
+    extracted_rules.push_back({ pair.first, extractor.apply(pair.second) });
 
   size_t i = 0;
   for (auto &pair : extracted_rules) {
     auto &rule = pair.second;
     auto symbol = dynamic_pointer_cast<const Symbol>(rule);
-    if (symbol.get() && symbol->is_auxiliary() && extractor.token_usage_counts[symbol->index] == 1) {
-      lexical_grammar.rules.push_back({pair.first, extractor.tokens[symbol->index].second});
+    if (symbol.get() && symbol->is_auxiliary() &&
+        extractor.token_usage_counts[symbol->index] == 1) {
+      lexical_grammar.rules.push_back(
+        { pair.first, extractor.tokens[symbol->index].second });
       extractor.token_usage_counts[symbol->index] = 0;
       symbol_replacer.replacements.insert(
         { Symbol(i),
diff --git a/src/compiler/prepare_grammar/is_token.cc b/src/compiler/prepare_grammar/is_token.cc
index b7d14a7e..488d49d0 100644
--- a/src/compiler/prepare_grammar/is_token.cc
+++ b/src/compiler/prepare_grammar/is_token.cc
@@ -9,14 +9,20 @@ namespace tree_sitter {
 namespace prepare_grammar {
 
 class IsToken : public rules::RuleFn<bool> {
-  bool apply_to(const rules::String *rule) { return true; }
-  bool apply_to(const rules::Pattern *rule) { return true; }
+  bool apply_to(const rules::String *rule) {
+    return true;
+  }
+  bool apply_to(const rules::Pattern *rule) {
+    return true;
+  }
   bool apply_to(const rules::Metadata *rule) {
     return rule->value_for(rules::IS_TOKEN);
   }
 };
 
-bool is_token(const rules::rule_ptr &rule) { return IsToken().apply(rule); }
+bool is_token(const rules::rule_ptr &rule) {
+  return IsToken().apply(rule);
+}
 
 }  // namespace prepare_grammar
 }  // namespace tree_sitter
diff --git a/src/compiler/prepare_grammar/parse_regex.cc b/src/compiler/prepare_grammar/parse_regex.cc
index 4ff0d99b..823f7bb5 100644
--- a/src/compiler/prepare_grammar/parse_regex.cc
+++ b/src/compiler/prepare_grammar/parse_regex.cc
@@ -211,9 +211,13 @@ class PatternParser {
     iter += lookahead_size;
   }
 
-  uint32_t peek() { return lookahead; }
+  uint32_t peek() {
+    return lookahead;
+  }
 
-  bool has_more_input() { return lookahead && iter <= end; }
+  bool has_more_input() {
+    return lookahead && iter <= end;
+  }
 
   pair<rule_ptr, const GrammarError *> error(string msg) {
     return { blank(), new GrammarError(GrammarErrorTypeRegex, msg) };
diff --git a/src/compiler/prepare_grammar/token_description.cc b/src/compiler/prepare_grammar/token_description.cc
index 54c00562..19877708 100644
--- a/src/compiler/prepare_grammar/token_description.cc
+++ b/src/compiler/prepare_grammar/token_description.cc
@@ -22,7 +22,9 @@ class TokenDescription : public rules::RuleFn<string> {
     return "STR_" + util::escape_string(rule->value);
   }
 
-  string apply_to(const rules::Metadata *rule) { return apply(rule->rule); }
+  string apply_to(const rules::Metadata *rule) {
+    return apply(rule->rule);
+  }
 
   string apply_to(const rules::Seq *rule) {
     return "(seq " + apply(rule->left) + " " + apply(rule->right) + ")";
diff --git a/src/compiler/rules/blank.cc b/src/compiler/rules/blank.cc
index 64a5d891..4281eba6 100644
--- a/src/compiler/rules/blank.cc
+++ b/src/compiler/rules/blank.cc
@@ -11,13 +11,21 @@ bool Blank::operator==(const Rule &rule) const {
   return dynamic_cast<const Blank *>(&rule) != nullptr;
 }
 
-size_t Blank::hash_code() const { return 0; }
+size_t Blank::hash_code() const {
+  return 0;
+}
 
-rule_ptr Blank::copy() const { return std::make_shared<Blank>(); }
+rule_ptr Blank::copy() const {
+  return std::make_shared<Blank>();
+}
 
-std::string Blank::to_string() const { return "(blank)"; }
+std::string Blank::to_string() const {
+  return "(blank)";
+}
 
-void Blank::accept(Visitor *visitor) const { visitor->visit(this); }
+void Blank::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/built_in_symbols.cc b/src/compiler/rules/built_in_symbols.cc
index 7a648a3d..92c14866 100644
--- a/src/compiler/rules/built_in_symbols.cc
+++ b/src/compiler/rules/built_in_symbols.cc
@@ -3,10 +3,21 @@
 namespace tree_sitter {
 namespace rules {
 
-Symbol END_OF_INPUT() { return Symbol(-1, SymbolOptionToken); }
-Symbol ERROR() { return Symbol(-2, SymbolOptionToken); }
-Symbol START() { return Symbol(-3); }
-Symbol DOCUMENT() { return Symbol(-4); }
+Symbol END_OF_INPUT() {
+  return Symbol(-1, SymbolOptionToken);
+}
+
+Symbol ERROR() {
+  return Symbol(-2, SymbolOptionToken);
+}
+
+Symbol START() {
+  return Symbol(-3);
+}
+
+Symbol DOCUMENT() {
+  return Symbol(-4);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/character_set.cc b/src/compiler/rules/character_set.cc
index 3e50ed87..d18808ee 100644
--- a/src/compiler/rules/character_set.cc
+++ b/src/compiler/rules/character_set.cc
@@ -140,9 +140,13 @@ CharacterSet &CharacterSet::exclude(uint32_t min, uint32_t max) {
   return *this;
 }
 
-CharacterSet &CharacterSet::include(uint32_t c) { return include(c, c); }
+CharacterSet &CharacterSet::include(uint32_t c) {
+  return include(c, c);
+}
 
-CharacterSet &CharacterSet::exclude(uint32_t c) { return exclude(c, c); }
+CharacterSet &CharacterSet::exclude(uint32_t c) {
+  return exclude(c, c);
+}
 
 bool CharacterSet::is_empty() const {
   return !includes_all && included_chars.empty();
@@ -186,7 +190,9 @@ vector<CharacterRange> CharacterSet::excluded_ranges() const {
   return consolidate_ranges(excluded_chars);
 }
 
-void CharacterSet::accept(Visitor *visitor) const { visitor->visit(this); }
+void CharacterSet::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/choice.cc b/src/compiler/rules/choice.cc
index 15b3e76c..b4b08e9e 100644
--- a/src/compiler/rules/choice.cc
+++ b/src/compiler/rules/choice.cc
@@ -57,7 +57,9 @@ size_t Choice::hash_code() const {
   return result;
 }
 
-rule_ptr Choice::copy() const { return std::make_shared<Choice>(*this); }
+rule_ptr Choice::copy() const {
+  return std::make_shared<Choice>(*this);
+}
 
 string Choice::to_string() const {
   string result = "(choice";
@@ -66,7 +68,9 @@ string Choice::to_string() const {
   return result + ")";
 }
 
-void Choice::accept(Visitor *visitor) const { visitor->visit(this); }
+void Choice::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/metadata.cc b/src/compiler/rules/metadata.cc
index 17f61a7b..d3d56748 100644
--- a/src/compiler/rules/metadata.cc
+++ b/src/compiler/rules/metadata.cc
@@ -40,7 +40,9 @@ std::string Metadata::to_string() const {
   return "(metadata " + rule->to_string() + ")";
 }
 
-void Metadata::accept(Visitor *visitor) const { visitor->visit(this); }
+void Metadata::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/named_symbol.cc b/src/compiler/rules/named_symbol.cc
index 8423fc9a..b5afe89f 100644
--- a/src/compiler/rules/named_symbol.cc
+++ b/src/compiler/rules/named_symbol.cc
@@ -15,15 +15,21 @@ bool NamedSymbol::operator==(const Rule &rule) const {
   return other && other->name == name;
 }
 
-size_t NamedSymbol::hash_code() const { return hash<string>()(name); }
+size_t NamedSymbol::hash_code() const {
+  return hash<string>()(name);
+}
 
 rule_ptr NamedSymbol::copy() const {
   return std::make_shared<NamedSymbol>(*this);
 }
 
-string NamedSymbol::to_string() const { return string("(sym '") + name + "')"; }
+string NamedSymbol::to_string() const {
+  return string("(sym '") + name + "')";
+}
 
-void NamedSymbol::accept(Visitor *visitor) const { visitor->visit(this); }
+void NamedSymbol::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/pattern.cc b/src/compiler/rules/pattern.cc
index 536391c9..1d6fff39 100644
--- a/src/compiler/rules/pattern.cc
+++ b/src/compiler/rules/pattern.cc
@@ -16,15 +16,21 @@ bool Pattern::operator==(tree_sitter::rules::Rule const &other) const {
   return pattern && (pattern->value == value);
 }
 
-size_t Pattern::hash_code() const { return hash<string>()(value); }
+size_t Pattern::hash_code() const {
+  return hash<string>()(value);
+}
 
-rule_ptr Pattern::copy() const { return std::make_shared<Pattern>(*this); }
+rule_ptr Pattern::copy() const {
+  return std::make_shared<Pattern>(*this);
+}
 
 string Pattern::to_string() const {
   return string("(pattern '") + util::escape_string(value) + "')";
 }
 
-void Pattern::accept(Visitor *visitor) const { visitor->visit(this); }
+void Pattern::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/repeat.cc b/src/compiler/rules/repeat.cc
index 71fa32df..40f41ed3 100644
--- a/src/compiler/rules/repeat.cc
+++ b/src/compiler/rules/repeat.cc
@@ -25,15 +25,21 @@ bool Repeat::operator==(const Rule &rule) const {
   return other && (*other->content == *content);
 }
 
-size_t Repeat::hash_code() const { return content->hash_code(); }
+size_t Repeat::hash_code() const {
+  return content->hash_code();
+}
 
-rule_ptr Repeat::copy() const { return make_shared<Repeat>(*this); }
+rule_ptr Repeat::copy() const {
+  return make_shared<Repeat>(*this);
+}
 
 string Repeat::to_string() const {
   return string("(repeat ") + content->to_string() + ")";
 }
 
-void Repeat::accept(Visitor *visitor) const { visitor->visit(this); }
+void Repeat::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/rules.cc b/src/compiler/rules/rules.cc
index 8770e98c..89f9bf64 100644
--- a/src/compiler/rules/rules.cc
+++ b/src/compiler/rules/rules.cc
@@ -28,23 +28,37 @@ static rule_ptr metadata(rule_ptr rule, map<MetadataKey, int> values) {
   return std::make_shared<Metadata>(rule, values);
 }
 
-rule_ptr blank() { return make_shared<Blank>(); }
+rule_ptr blank() {
+  return make_shared<Blank>();
+}
 
-rule_ptr choice(const vector<rule_ptr> &rules) { return Choice::build(rules); }
+rule_ptr choice(const vector<rule_ptr> &rules) {
+  return Choice::build(rules);
+}
 
-rule_ptr repeat(const rule_ptr &content) { return Repeat::build(content); }
+rule_ptr repeat(const rule_ptr &content) {
+  return Repeat::build(content);
+}
 
-rule_ptr seq(const vector<rule_ptr> &rules) { return Seq::build(rules); }
+rule_ptr seq(const vector<rule_ptr> &rules) {
+  return Seq::build(rules);
+}
 
-rule_ptr sym(const string &name) { return make_shared<NamedSymbol>(name); }
+rule_ptr sym(const string &name) {
+  return make_shared<NamedSymbol>(name);
+}
 
-rule_ptr pattern(const string &value) { return make_shared<Pattern>(value); }
+rule_ptr pattern(const string &value) {
+  return make_shared<Pattern>(value);
+}
 
 rule_ptr str(const string &value) {
   return token(prec(1, make_shared<String>(value)));
 }
 
-rule_ptr err(const rule_ptr &rule) { return choice({ rule, ERROR().copy() }); }
+rule_ptr err(const rule_ptr &rule) {
+  return choice({ rule, ERROR().copy() });
+}
 
 rule_ptr prec(int precedence, const rule_ptr &rule, Associativity associativity) {
   return metadata(
diff --git a/src/compiler/rules/seq.cc b/src/compiler/rules/seq.cc
index bd5aa06b..54dc5821 100644
--- a/src/compiler/rules/seq.cc
+++ b/src/compiler/rules/seq.cc
@@ -25,15 +25,21 @@ bool Seq::operator==(const Rule &rule) const {
   return other && (*other->left == *left) && (*other->right == *right);
 }
 
-size_t Seq::hash_code() const { return left->hash_code() ^ right->hash_code(); }
+size_t Seq::hash_code() const {
+  return left->hash_code() ^ right->hash_code();
+}
 
-rule_ptr Seq::copy() const { return std::make_shared<Seq>(*this); }
+rule_ptr Seq::copy() const {
+  return std::make_shared<Seq>(*this);
+}
 
 string Seq::to_string() const {
   return string("(seq ") + left->to_string() + " " + right->to_string() + ")";
 }
 
-void Seq::accept(Visitor *visitor) const { visitor->visit(this); }
+void Seq::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/string.cc b/src/compiler/rules/string.cc
index 250b70cb..075a4267 100644
--- a/src/compiler/rules/string.cc
+++ b/src/compiler/rules/string.cc
@@ -15,13 +15,21 @@ bool String::operator==(const Rule &rule) const {
   return other && (other->value == value);
 }
 
-size_t String::hash_code() const { return hash<string>()(value); }
+size_t String::hash_code() const {
+  return hash<string>()(value);
+}
 
-rule_ptr String::copy() const { return std::make_shared<String>(*this); }
+rule_ptr String::copy() const {
+  return std::make_shared<String>(*this);
+}
 
-string String::to_string() const { return string("(string '") + value + "')"; }
+string String::to_string() const {
+  return string("(string '") + value + "')";
+}
 
-void String::accept(Visitor *visitor) const { visitor->visit(this); }
+void String::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/symbol.cc b/src/compiler/rules/symbol.cc
index ac7b5986..b9f213f2 100644
--- a/src/compiler/rules/symbol.cc
+++ b/src/compiler/rules/symbol.cc
@@ -31,7 +31,9 @@ size_t Symbol::hash_code() const {
   return hash<int>()(index) ^ hash<int16_t>()(options);
 }
 
-rule_ptr Symbol::copy() const { return std::make_shared<Symbol>(*this); }
+rule_ptr Symbol::copy() const {
+  return std::make_shared<Symbol>(*this);
+}
 
 string Symbol::to_string() const {
   string name = (options & SymbolOptionAuxiliary) ? "aux_" : "";
@@ -47,13 +49,21 @@ bool Symbol::operator<(const Symbol &other) const {
   return (index < other.index);
 }
 
-bool Symbol::is_token() const { return options & SymbolOptionToken; }
+bool Symbol::is_token() const {
+  return options & SymbolOptionToken;
+}
 
-bool Symbol::is_built_in() const { return index < 0; }
+bool Symbol::is_built_in() const {
+  return index < 0;
+}
 
-bool Symbol::is_auxiliary() const { return options & SymbolOptionAuxiliary; }
+bool Symbol::is_auxiliary() const {
+  return options & SymbolOptionAuxiliary;
+}
 
-void Symbol::accept(Visitor *visitor) const { visitor->visit(this); }
+void Symbol::accept(Visitor *visitor) const {
+  visitor->visit(this);
+}
 
 }  // namespace rules
 }  // namespace tree_sitter
diff --git a/src/compiler/rules/visitor.h b/src/compiler/rules/visitor.h
index 66dfd4b2..b1331b48 100644
--- a/src/compiler/rules/visitor.h
+++ b/src/compiler/rules/visitor.h
@@ -42,49 +42,89 @@ class RuleFn : private Visitor {
   }
 
  protected:
-  virtual T default_apply(const Rule *rule) { return T(); }
+  virtual T default_apply(const Rule *rule) {
+    return T();
+  }
 
   virtual T apply_to(const Blank *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const CharacterSet *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const Choice *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const Metadata *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const Pattern *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const Repeat *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const Seq *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const String *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const NamedSymbol *rule) {
     return default_apply((const Rule *)rule);
   }
+
   virtual T apply_to(const Symbol *rule) {
     return default_apply((const Rule *)rule);
   }
 
-  void visit(const Blank *rule) { value_ = apply_to(rule); }
-  void visit(const CharacterSet *rule) { value_ = apply_to(rule); }
-  void visit(const Choice *rule) { value_ = apply_to(rule); }
-  void visit(const Metadata *rule) { value_ = apply_to(rule); }
-  void visit(const Pattern *rule) { value_ = apply_to(rule); }
-  void visit(const Repeat *rule) { value_ = apply_to(rule); }
-  void visit(const Seq *rule) { value_ = apply_to(rule); }
-  void visit(const String *rule) { value_ = apply_to(rule); }
-  void visit(const NamedSymbol *rule) { value_ = apply_to(rule); }
-  void visit(const Symbol *rule) { value_ = apply_to(rule); }
+  void visit(const Blank *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const CharacterSet *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const Choice *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const Metadata *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const Pattern *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const Repeat *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const Seq *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const String *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const NamedSymbol *rule) {
+    value_ = apply_to(rule);
+  }
+
+  void visit(const Symbol *rule) {
+    value_ = apply_to(rule);
+  }
 
  private:
   T value_;