diff -r 000000000000 -r c52ca92aa593 src/YAMLHandler.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/YAMLHandler.h	Wed Dec 23 17:15:34 2020 +0100
@@ -0,0 +1,75 @@
+/**
+ * Relational pipes
+ * Copyright © 2018 František Kučera (Frantovo.cz, GlobalCode.info)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <memory>
+#include <string>
+#include <vector>
+#include <iostream>
+#include <sstream>
+#include <locale>
+#include <codecvt>
+
+#include <relpipe/common/type/typedefs.h>
+#include <relpipe/reader/TypeId.h>
+#include <relpipe/reader/handlers/RelationalReaderStringHandler.h>
+#include <relpipe/reader/handlers/AttributeMetadata.h>
+
+namespace relpipe {
+namespace out {
+namespace yaml {
+
+class YAMLHandler : public relpipe::reader::handlers::RelationalReaderStringHandler {
+private:
+	std::ostream& output;
+	std::wstring_convert<std::codecvt_utf8<wchar_t>> convertor; // we generate YAML always in UTF-8 like XML?
+	std::vector<relpipe::reader::handlers::AttributeMetadata> currentAttributes;
+	size_t currentAttributeIndex = 0;
+
+	void writeYamlValue(const relpipe::common::type::StringX& value) {
+		// TODO: escaping
+		output << convertor.to_bytes(value);
+	}
+public:
+
+	YAMLHandler(std::ostream& output) : output(output) {
+	}
+
+	void startRelation(relpipe::common::type::StringX name, std::vector<relpipe::reader::handlers::AttributeMetadata> attributes) override {
+		currentAttributes = attributes;
+	}
+
+	void attribute(const relpipe::common::type::StringX& value) override {
+		if (currentAttributeIndex % currentAttributes.size() == 0) {
+			currentAttributeIndex = 0;
+			
+		} else {
+			
+		}
+
+		currentAttributeIndex++;
+	}
+
+	void endOfPipe() {
+		output.flush();
+	}
+
+};
+
+}
+}
+}