Simplify hashing of rules

src/compiler/build_tables/item.h

@@ -51,7 +51,7 @@ namespace std {
         size_t operator()(const tree_sitter::build_tables::Item &item) const {
             return
                 hash<tree_sitter::rules::Symbol>()(item.lhs) ^
-                hash<tree_sitter::rules::Rule>()(*item.rule);
+                hash<tree_sitter::rules::rule_ptr>()(item.rule);
         }
     };
 
@@ -60,7 +60,7 @@ namespace std {
         size_t operator()(const tree_sitter::build_tables::ParseItem &item) const {
             return
             hash<string>()(item.lhs.name) ^
-            hash<tree_sitter::rules::Rule>()(*item.rule) ^
+            hash<tree_sitter::rules::rule_ptr>()(item.rule) ^
             hash<size_t>()(item.consumed_symbols.size()) ^
             hash<string>()(item.lookahead_sym.name);
         }

src/compiler/rules/blank.cpp

@@ -9,7 +9,7 @@ namespace tree_sitter  {
         }
         
         size_t Blank::hash_code() const {
-            return typeid(this).hash_code();
+            return 0;
         }
         
         rule_ptr Blank::copy() const {

src/compiler/rules/character_set.cpp

@@ -69,7 +69,12 @@ namespace tree_sitter  {
         }
         
         size_t CharacterSet::hash_code() const {
-            return typeid(this).hash_code() ^ hash<string>()(to_string());
+            size_t result = std::hash<size_t>()(ranges.size());
+            for (auto &range : ranges) {
+                result ^= std::hash<char>()(range.min);
+                result ^= std::hash<char>()(range.max);
+            }
+            return result;
         }
 
         rule_ptr CharacterSet::copy() const {

src/compiler/rules/character_set.h

@@ -57,7 +57,11 @@ namespace tree_sitter  {
 
 namespace std {
     template<>
-    struct hash<tree_sitter::rules::CharacterSet> : hash<tree_sitter::rules::Rule> {};
+    struct hash<tree_sitter::rules::CharacterSet> {
+        size_t operator()(const tree_sitter::rules::CharacterSet &rule) const {
+            return rule.hash_code();
+        }
+    };
 }
 
 #endif

src/compiler/rules/choice.cpp

@@ -12,7 +12,7 @@ namespace tree_sitter  {
         }
 
         size_t Choice::hash_code() const {
-            return typeid(this).hash_code() ^ left->hash_code() ^ right->hash_code();
+            return left->hash_code() ^ right->hash_code();
         }
         
         rule_ptr Choice::copy() const {

src/compiler/rules/pattern.cpp

@@ -146,7 +146,7 @@ namespace tree_sitter {
         }
         
         size_t Pattern::hash_code() const {
-            return typeid(this).hash_code() ^ hash<string>()(value);
+            return hash<string>()(value);
         }
         
         rule_ptr Pattern::copy() const {

src/compiler/rules/repeat.cpp

@@ -12,7 +12,7 @@ namespace tree_sitter {
         }
         
         size_t Repeat::hash_code() const {
-            return typeid(this).hash_code() ^ content->hash_code();
+            return content->hash_code();
         }
         
         rule_ptr Repeat::copy() const {

src/compiler/rules/rule.h

@@ -27,9 +27,9 @@ namespace tree_sitter {
 
 namespace std {
     template<>
-    struct hash<tree_sitter::rules::Rule> {
-        size_t operator()(const tree_sitter::rules::Rule &rule) const {
-            return rule.hash_code();
+    struct hash<tree_sitter::rules::rule_ptr> {
+        size_t operator()(const tree_sitter::rules::rule_ptr &rule) const {
+            return typeid(*rule).hash_code() ^ rule->hash_code();
         }
     };
 }

src/compiler/rules/seq.cpp

@@ -12,7 +12,7 @@ namespace tree_sitter {
         }
         
         size_t Seq::hash_code() const {
-            return typeid(this).hash_code() ^ left->hash_code() ^ right->hash_code();
+            return left->hash_code() ^ right->hash_code();
         }
         
         rule_ptr Seq::copy() const {

src/compiler/rules/string.cpp

@@ -13,7 +13,7 @@ namespace tree_sitter  {
         }
                 
         size_t String::hash_code() const {
-            return typeid(this).hash_code() ^ hash<string>()(value);
+            return hash<string>()(value);
         }
         
         rule_ptr String::copy() const {

src/compiler/rules/symbol.cpp

@@ -18,7 +18,7 @@ namespace tree_sitter  {
         }
 
         size_t Symbol::hash_code() const {
-            return typeid(this).hash_code() ^ hash<string>()(name) ^ hash<bool>()(is_auxiliary);
+            return hash<string>()(name) ^ hash<bool>()(is_auxiliary);
         }
         
         rule_ptr Symbol::copy() const {

src/compiler/rules/symbol.h

@@ -2,6 +2,7 @@
 #define __tree_sitter__sym__
 
 #include "rule.h"
+#include <map>
 
 namespace tree_sitter  {
     namespace rules {
@@ -27,7 +28,11 @@ namespace tree_sitter  {
 
 namespace std {
     template<>
-    struct hash<tree_sitter::rules::Symbol> : hash<tree_sitter::rules::Rule> {};
+    struct hash<tree_sitter::rules::Symbol> {
+        size_t operator()(const tree_sitter::rules::Symbol &rule) const {
+            return rule.hash_code();
+        }
+    };
 }