diff --git a/examples/grammars/golang.cc b/examples/grammars/golang.cc
index bd1749f5..e9627da9 100644
--- a/examples/grammars/golang.cc
+++ b/examples/grammars/golang.cc
@@ -8,7 +8,7 @@ namespace tree_sitter_examples {
         return seq({ element, repeat(seq({ str(","), element })) });
     }
     
-    static rule_ptr comma_sep(const rule_ptr &element) {
+    static rule_ptr comma_sep(rule_ptr element) {
         return choice({ comma_sep1(element), blank() });
     }
     
diff --git a/examples/grammars/javascript.cc b/examples/grammars/javascript.cc
index 3cf10251..00e3d82c 100644
--- a/examples/grammars/javascript.cc
+++ b/examples/grammars/javascript.cc
@@ -4,11 +4,11 @@ namespace tree_sitter_examples {
     using tree_sitter::Grammar;
     using namespace tree_sitter::rules;
 
-    static rule_ptr optional(const rule_ptr &rule) {
+    static rule_ptr optional(rule_ptr rule) {
         return choice({ rule, blank() });
     }
 
-    static rule_ptr comma_sep(const rule_ptr &element) {
+    static rule_ptr comma_sep(rule_ptr element) {
         return choice({
             seq({ element, repeat(seq({ str(","), element })) }),
             blank(),
diff --git a/examples/grammars/json.cc b/examples/grammars/json.cc
index 7ef6db19..fd09f96f 100644
--- a/examples/grammars/json.cc
+++ b/examples/grammars/json.cc
@@ -4,7 +4,7 @@ namespace tree_sitter_examples {
     using tree_sitter::Grammar;
     using namespace tree_sitter::rules;
 
-    static rule_ptr comma_sep(const rule_ptr &rule) {
+    static rule_ptr comma_sep(rule_ptr rule) {
         return choice({
             seq({ rule, repeat(seq({ str(","), rule })) }),
             blank(),