diff -r 000000000000 -r f36bf14d45cb src/GuileHandler.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/GuileHandler.h	Sat Jan 19 16:01:08 2019 +0100
@@ -0,0 +1,113 @@
+/**
+ * Relational pipes
+ * Copyright © 2019 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 <regex>
+
+#include <relpipe/reader/typedefs.h>
+#include <relpipe/reader/TypeId.h>
+#include <relpipe/reader/handlers/RelationalReaderStringHandler.h>
+#include <relpipe/reader/handlers/AttributeMetadata.h>
+
+#include <relpipe/writer/Factory.h>
+
+#include <relpipe/cli/RelpipeCLIException.h>
+
+namespace relpipe {
+namespace tr {
+namespace guile {
+
+using namespace std;
+using namespace relpipe;
+using namespace relpipe::reader;
+using namespace relpipe::reader::handlers;
+
+class GuileHandler : public RelationalReaderStringHadler {
+private:
+	shared_ptr<writer::RelationalWriter> relationalWriter;
+
+	wregex relationNameRegEx;
+
+	vector<AttributeMetadata> currentMetadata;
+	vector<string_t> currentRecord;
+	integer_t currentAttributeIndex = 0;
+	boolean_t includeCurrentRecord = false;
+	boolean_t filterCurrentRelation = false;
+
+public:
+
+	GuileHandler(ostream& output, const vector<string_t>& arguments) {
+		relationalWriter.reset(writer::Factory::create(output));
+
+		// TODO: options and parser
+		if (arguments.size() == 1) {
+			relationNameRegEx = wregex(arguments[0]);
+		} else {
+			throw cli::RelpipeCLIException(L"Usage: relpipe-tr-guile <relationNameRegExp>", cli::CLI::EXIT_CODE_UNKNOWN_COMMAND);
+		}
+	}
+
+	void startRelation(string_t name, vector<AttributeMetadata> attributes) override {
+		currentMetadata = attributes;
+		// TODO: move to a reusable method (or use same metadata on both reader and writer side?)
+		vector<writer::AttributeMetadata> writerMetadata;
+		for (AttributeMetadata readerMetadata : attributes) {
+			writerMetadata.push_back({readerMetadata.getAttributeName(), relationalWriter->toTypeId(readerMetadata.getTypeName())});
+		}
+		
+		currentRecord.resize(attributes.size());
+		filterCurrentRelation = regex_match(name, relationNameRegEx);
+
+		relationalWriter->startRelation(name, writerMetadata, true);
+	}
+
+	void attribute(const string_t& value) override {
+		if (filterCurrentRelation) {
+			// TODO: evaluate condition and updates in Guile
+			currentRecord[currentAttributeIndex] = value;
+			includeCurrentRecord = false;
+
+			currentAttributeIndex++;
+
+			if (currentAttributeIndex > 0 && currentAttributeIndex % currentMetadata.size() == 0) {
+				if (includeCurrentRecord) for (string_t v : currentRecord) relationalWriter->writeAttribute(v);
+				includeCurrentRecord = false;
+			}
+
+			currentAttributeIndex = currentAttributeIndex % currentMetadata.size();
+		} else {
+			relationalWriter->writeAttribute(value);
+		}
+	}
+
+	void endOfPipe() {
+
+	}
+
+};
+
+}
+}
+}