Add 'libnbtplusplus/' from commit '1a0ffe372f4da8408c5d08a36013536a3396b9e6'

git-subtree-dir: libnbtplusplus
git-subtree-mainline: 7fb132859fda54aa96bc9dd46d302b343eeb5a02
git-subtree-split: 1a0ffe372f4da8408c5d08a36013536a3396b9e6

1 files changed, 75 insertions, 0 deletions

diff --git a/libnbtplusplus/include/value_initializer.h b/libnbtplusplus/include/value_initializer.h
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+++ b/libnbtplusplus/include/value_initializer.h
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+/*
+ * SPDX-FileCopyrightText: 2013, 2015 ljfa-ag <ljfa-ag@web.de>
+ *
+ * SPDX-License-Identifier: LGPL-3.0-or-later
+ */
+
+/*
+ * libnbt++ - A library for the Minecraft Named Binary Tag format.
+ * Copyright (C) 2013, 2015  ljfa-ag
+ *
+ * This file is part of libnbt++.
+ *
+ * libnbt++ is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * libnbt++ 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with libnbt++.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef VALUE_INITIALIZER_H_INCLUDED
+#define VALUE_INITIALIZER_H_INCLUDED
+
+#include "value.h"
+
+namespace nbt
+{
+
+	/**
+	 * @brief Helper class for implicitly constructing value objects
+	 *
+	 * This type is a subclass of @ref value. However the only difference to
+	 * value is that this class has additional constructors which allow implicit
+	 * conversion of various types to value objects. These constructors are not
+	 * part of the value class itself because implicit conversions like this
+	 * (especially from @c tag&& to @c value) can cause problems and ambiguities
+	 * in some cases.
+	 *
+	 * value_initializer is especially useful as function parameter type, it
+	 * will allow convenient conversion of various values to tags on function
+	 * call.
+	 *
+	 * As value_initializer objects are in no way different than value objects,
+	 * they can just be converted to value after construction.
+	 */
+	class NBT_EXPORT value_initializer : public value
+	{
+	  public:
+		value_initializer(std::unique_ptr<tag>&& t) noexcept
+			: value(std::move(t))
+		{
+		}
+		value_initializer(std::nullptr_t) noexcept : value(nullptr) {}
+		value_initializer(value&& val) noexcept : value(std::move(val)) {}
+		value_initializer(tag&& t) : value(std::move(t)) {}
+
+		value_initializer(int8_t val);
+		value_initializer(int16_t val);
+		value_initializer(int32_t val);
+		value_initializer(int64_t val);
+		value_initializer(float val);
+		value_initializer(double val);
+		value_initializer(const std::string& str);
+		value_initializer(std::string&& str);
+		value_initializer(const char* str);
+	};
+
+} // namespace nbt
+
+#endif // VALUE_INITIALIZER_H_INCLUDED