added save_file and save_string methods

janssonxx.h

@@ -49,6 +49,16 @@ public:
 		return Value().take_ownership(json_loads(string, error));
 	}
 
+	// write the value to a file
+	int save_file(const char* path, int flags = JSON_INDENT(2)) const {
+		return json_dump_file(_value, path, flags);
+	}
+
+	// write the value to a string (caller must deallocate with free()!)
+	char* save_string(int flags = JSON_INDENT(2)) const {
+		return json_dumps(_value, flags);
+	}
+
 	// construct Value from input
 	static Value from(const char* value) { return Value().take_ownership(json_string(value)); }
 	static Value from(const std::string& value) { return from(value.c_str()); }

test.cc

@@ -1,5 +1,6 @@
 #include <iostream>
 #include <iomanip>
+#include <malloc.h>
 
 #include "janssonxx.h"
 
@@ -108,5 +109,13 @@ int main() {
 	e3.clear();
 	ASSERT_EQ(e3.size(), 0, "e3 has incorrect number of properties after clear");
 
+	e3 = jansson::Value::object();
+	e3.set("foo", jansson::Value::from("test"));
+	e3.set("bar", jansson::Value::from(3));
+	char* out_cstr = e3.save_string(0);
+	string out(out_cstr);
+	free(out_cstr);
+	ASSERT_EQ(out, "{\"bar\": 3,\"foo\": \"test\"}\n", "object did not serialize as expected");
+
 	return 0;
 }