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diff --git a/include/raul/Symbol.hpp b/include/raul/Symbol.hpp
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+/*
+  This file is part of Raul.
+  Copyright 2007-2014 David Robillard <http://drobilla.net>
+
+  Raul 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 any later version.
+
+  Raul 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 Raul.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef RAUL_SYMBOL_HPP
+#define RAUL_SYMBOL_HPP
+
+#include "raul/Exception.hpp"
+
+#include <string>
+
+namespace Raul {
+
+/** A restricted string which is a valid C identifier and Path component.
+ *
+ * A Symbol is a very restricted string suitable for use as an identifier.
+ * It is a valid LV2 symbol, URI fragment, filename, OSC path fragment,
+ * and identifier for virtually all programming languages.
+ *
+ * Valid characters are _, a-z, A-Z, 0-9, except the first character which
+ * must not be 0-9.
+ *
+ * @ingroup raul
+ */
+class Symbol : public std::basic_string<char> {
+public:
+	/** Attempt to construct an invalid Symbol. */
+	class BadSymbol : public Exception {
+	public:
+		explicit BadSymbol(const std::string& symbol) : Exception(symbol) {}
+	};
+
+	/** Construct a Symbol from a C++ string.
+	 *
+	 * This will throw an exception if `symbol` is invalid.  To avoid this,
+	 * use is_valid() first to check.
+	 */
+	explicit Symbol(const std::basic_string<char>& symbol)
+		: std::basic_string<char>(symbol)
+	{
+		if (!is_valid(symbol)) {
+			throw BadSymbol(symbol);
+		}
+	}
+
+	/** Construct a Symbol from a C string.
+	 *
+	 * This will throw an exception if `symbol` is invalid.  To avoid this,
+	 * use is_valid() first to check.
+	 */
+	explicit Symbol(const char* symbol)
+		: std::basic_string<char>(symbol)
+	{
+		if (!is_valid(symbol)) {
+			throw BadSymbol(symbol);
+		}
+	}
+
+	/** Copy a Symbol.
+	 *
+	 * Note this is faster than constructing a Symbol from another Symbol's
+	 * string since validation is unnecessary.
+	 */
+	Symbol(const Symbol& symbol) = default;
+
+	/** Return true iff `c` is a valid Symbol start character. */
+	static inline bool is_valid_start_char(char c) {
+		return (c == '_') || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
+	}
+
+	/** Return true iff `c` is a valid Symbol character. */
+	static inline bool is_valid_char(char c) {
+		return is_valid_start_char(c) || (c >= '0' && c <= '9');
+	}
+
+	/** Return true iff `str` is a valid Symbol. */
+	static inline bool is_valid(const std::basic_string<char>& str) {
+		if (str.empty() || (str[0] >= '0' && str[0] <= '9')) {
+			return false;  // Must start with a letter or underscore
+		}
+
+		for (auto c : str) {
+			if (!is_valid_char(c)) {
+				return false;  // All characters must be _, a-z, A-Z, 0-9
+			}
+		}
+
+		return true;
+	}
+
+	/** Convert a string to a valid symbol.
+	 *
+	 * This will make a best effort at turning `str` into a complete, valid
+	 * Symbol, and will always return one.
+	 */
+	static inline Symbol symbolify(const std::basic_string<char>& in) {
+		if (in.empty()) {
+			return Symbol("_");
+		}
+
+		std::basic_string<char> out(in);
+		for (size_t i = 0; i < in.length(); ++i) {
+			if (!is_valid_char(out[i])) {
+				out[i] = '_';
+			}
+		}
+
+		if (is_valid_start_char(out[0])) {
+			return Symbol(out);
+		} else {
+			return Symbol(std::string("_") + out);
+		}
+	}
+};
+
+} // namespace Raul
+
+#endif // RAUL_SYMBOL_HPP