diff --git a/include/rjp.h b/include/rjp.h
index 61707c1..0b9e9a0 100644
--- a/include/rjp.h
+++ b/include/rjp.h
@@ -99,10 +99,14 @@ void* rjp_calloc(size_t num, size_t nbytes);
 void rjp_free(void* dest);
 
 //add a member to a json object
-RJP_value* rjp_add_member(RJP_value* dest, int alloc_key, char* key, size_t keylen, RJP_value value);
+RJP_value* rjp_add_member(RJP_value* dest, const char* key, size_t keylen, RJP_value value);
+RJP_value* rjp_add_member_no_alloc(RJP_value* dest, char* key, size_t keylen, RJP_value value);
 //add an element to a json array
 RJP_value* rjp_add_element(RJP_value* dest, RJP_value value);
 
+//set existing value
+void rjp_set_value(RJP_value* dest, RJP_value value);
+
 //initialize a RJP_value to the requested type and value
 RJP_value rjp_integer(long i);
 RJP_value rjp_boolean(char b);
diff --git a/include/rjp_internal.h b/include/rjp_internal.h
index 7fc4ff8..a358cdf 100644
--- a/include/rjp_internal.h
+++ b/include/rjp_internal.h
@@ -23,7 +23,7 @@
 
 char* _rjp__parse_string(RJP_value* root, const char* str, int* len, int* row, int* column);
 size_t _rjp__object_strlen(RJP_value* root);
-void _rjp__add_member(RJP_object* j, char* str, size_t len);
+void _rjp__add_member(RJP_object* j, const char* str, size_t len);
 void _rjp__add_member_no_alloc(RJP_object* j, char* str, size_t len);
 void _rjp__add_element(RJP_array* j);
 size_t _rjp__object_strlen(RJP_value* root);
diff --git a/src/input.c b/src/input.c
index 1ccda5e..dbe1299 100644
--- a/src/input.c
+++ b/src/input.c
@@ -61,7 +61,7 @@ void _rjp__add_element(RJP_array* j){
 	}
 }
 //create member of the object as a linked list member and assign a name with name allocation
-void _rjp__add_member(RJP_object* j, char* str, size_t len){
+void _rjp__add_member(RJP_object* j, const char* str, size_t len){
 	++j->num_members;
 	if(!j->members){
 		j->members = rjp_calloc(1, sizeof(RJP_object_member));
diff --git a/src/output.c b/src/output.c
index c7050b4..584ef11 100644
--- a/src/output.c
+++ b/src/output.c
@@ -36,13 +36,18 @@ void* rjp_calloc(size_t num, size_t nbytes){
 void rjp_free(void* data){
 	free(data);
 }
-RJP_value* rjp_add_member(RJP_value* dest, int alloc_key, char* key, size_t keylen, RJP_value value){
+RJP_value* rjp_add_member(RJP_value* dest, const char* key, size_t keylen, RJP_value value){
 	if(!keylen)
 		keylen = strlen(key);
-	if(alloc_key)
-		_rjp__add_member(&dest->object, key, keylen);
-	else
-		_rjp__add_member_no_alloc(&dest->object, key, keylen);
+	_rjp__add_member(&dest->object, key, keylen);
+	dest->object.last->value = value;
+	dest->object.last->value.parent = dest;
+	return &dest->object.last->value;
+}
+RJP_value* rjp_add_member_no_alloc(RJP_value* dest, char* key, size_t keylen, RJP_value value){
+	if(!keylen)
+		keylen = strlen(key);
+	_rjp__add_member_no_alloc(&dest->object, key, keylen);
 	dest->object.last->value = value;
 	dest->object.last->value.parent = dest;
 	return &dest->object.last->value;
@@ -53,6 +58,11 @@ RJP_value* rjp_add_element(RJP_value* dest, RJP_value value){
 	dest->array.last->value.parent = dest;
 	return &dest->array.last->value;
 }
+void rjp_set_value(RJP_value* dest, RJP_value value){
+	struct RJP_value* p = dest->parent;
+	*dest = value;
+	dest->parent = p;
+}
 RJP_value rjp_integer(long i){
 	return (RJP_value){.integer = i, .type = json_integer};
 }