Make more things immutable

src/grammar.cpp

@@ -1,26 +1,14 @@
 #include "grammar.h"
 
-using namespace std;
-
 namespace tree_sitter {
-    Grammar::Grammar(const rule_map &rules, const std::string &start_rule_name) :
+    Grammar::Grammar(const rule_map_init_list &rules) :
         rules(rules),
-        start_rule_name(start_rule_name) {};
+        start_rule_name(rules.begin()->first) {}
 
-    std::unordered_map<std::string, rules::rule_ptr> build_rule_map(const initializer_list<string> &rule_names,
-                            const initializer_list<rules::rule_ptr> &rule_vals) {
-        std::unordered_map<std::string, rules::rule_ptr> result;
-        auto rule_name_i = rule_names.begin();
-        auto rule_i = rule_vals.begin();
-        while (rule_i != rule_vals.end()) {
-            result[*rule_name_i] = *rule_i;
-            rule_i++;
-            rule_name_i++;
-        }
-        return result;
+    const rules::rule_ptr Grammar::rule(const std::string &name) {
+        auto iter = rules.find(name);
+        return (iter == rules.end()) ?
+            rules::rule_ptr(nullptr) :
+            iter->second;
     }
-    
-    Grammar::Grammar(const initializer_list<string> &names, const initializer_list<rules::rule_ptr> &values) :
-        rules(build_rule_map(names, values)),
-        start_rule_name(*names.begin()) {}
 }

src/grammar.h

@@ -7,12 +7,15 @@
 namespace tree_sitter {
     class Grammar {
         typedef std::unordered_map<std::string, rules::rule_ptr> rule_map;
+        typedef std::initializer_list<std::pair<const std::string, rules::rule_ptr>> rule_map_init_list;
+
     public:
-        Grammar(const rule_map &rules, const std::string &start_rule_name);
-        Grammar(const std::initializer_list<std::string> &rule_names,
-                const std::initializer_list<rules::rule_ptr> &rules);
-        rule_map rules;
+        Grammar(const rule_map_init_list &rules);
+        const rules::rule_ptr rule(const std::string &);
         const std::string start_rule_name;
+
+    private:
+        const rule_map rules;
     };
 }
 

src/lr/item.cpp

@@ -11,7 +11,7 @@ namespace tree_sitter {
             consumed_sym_count(consumed_sym_count) {};
         
         Item Item::at_beginning_of_rule(const std::string &rule_name, Grammar &grammar) {
-            return Item(rule_name, grammar.rules[rule_name], 0);
+            return Item(rule_name, grammar.rule(rule_name), 0);
         }
         
         TransitionMap<Item> Item::transitions() const {

src/lr/item_set.cpp

@@ -57,6 +57,5 @@ namespace tree_sitter {
             stream << string(")");
             return stream;
         }
-        
     }
 }

src/rules/Pattern.h

@@ -13,7 +13,7 @@ namespace tree_sitter {
             bool operator==(const Rule& other) const;
             std::string to_string() const;
         private:
-            std::string value;
+            const std::string value;
         };
     }
 }

src/rules/char.h

@@ -12,7 +12,7 @@ namespace tree_sitter  {
             bool operator==(const Rule& other) const;
             std::string to_string() const;
         private:
-            char value;
+            const char value;
         };
     }
 }

src/rules/choice.h

@@ -12,8 +12,8 @@ namespace tree_sitter {
             bool operator==(const Rule& other) const;
             std::string to_string() const;
         private:
-            rule_ptr left;
-            rule_ptr right;
+            const rule_ptr left;
+            const rule_ptr right;
         };
     }
 }

src/rules/seq.h

@@ -12,8 +12,8 @@ namespace tree_sitter  {
             bool operator==(const Rule& other) const;
             std::string to_string() const;
         private:
-            rule_ptr left;
-            rule_ptr right;
+            const rule_ptr left;
+            const rule_ptr right;
         };
     }
 }

src/rules/string.h

@@ -13,7 +13,7 @@ namespace tree_sitter  {
             bool operator==(const Rule& other) const;
             std::string to_string() const;
         private:
-            std::string value;
+            const std::string value;
         };
     }
 }