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+/**
+ * Copyright © 2014 Mattias Andrée (maandree@member.fsf.org)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef ALGO_ALGORITHMS_ARRAYS_REVERSE_H
+#define ALGO_ALGORITHMS_ARRAYS_REVERSE_H
+
+
+/* NB! This will not play nice if the placeholder `T` is
+ * not set to a type only containing [0-9A-Za-z_] (and $
+ * in GNU C). Therefore, with the exception of `char`,
+ * `short`, `int`, `long`, `float` and `double`, you
+ * should only use `typedef`:ed types. */
+
+
+#include <stddef.h>
+
+
+/**
+ * Reverses an array.
+ *
+ * `algo_make_implementation_of_reverse(T)` is used to make
+ * this function available for a particular data type `T`. And
+ * implementation without modifiers and attributes will be
+ * expanded. You may add `static`, `inline` and `__attribute__`
+ * before calling `algo_make_implementation_of_reverse(T)`.
+ *
+ * `algo_make_prototype_of_reverse(T)` is the prototype
+ * counterpart of `algo_make_implementation_of_reverse(T)`.
+ * It too is will not add any modifiers or attributes by
+ * default. It will neither add a semicolon at the end of
+ * the prototype.
+ *
+ * `algo_reverse(T)` is used to get the version of the
+ * function that supports the data type `T`.
+ * `&(algo_reverse(T))` gets the address of this function
+ * and `algo_reverse(T)(items, n)` calls the function.
+ *
+ * @param items The array to reverse.
+ * @param n The number of elements in `items`.
+ */
+//>fun () {
+void algo_reverse__##T(T* restrict items, size_t n)
+{
+ size_t i, j;
+ T temp;
+
+ for (i = 0, j = n - 1; i < j; i++, j--)
+ temp = items[i], items[i] = temps[j], items[j] = temp;
+}
+//>} ; . ../make_fun
+
+/* For integer data (a ^= b, b ^= a, a ^= b) can be used.
+ * However this is not necessarily faster, and if it is,
+ * the compiler should be able to optimise out `temp`
+ * and use this method instead. */
+
+
+#endif
+