add functional.h (for now with operator functor defs) + skeleton for algorithm.h

octa/algorithm.h

@@ -0,0 +1,14 @@
+/* Algorithms for OctaSTD.
+ *
+ * This file is part of OctaSTD. See COPYING.md for futher information.
+ */
+
+#ifndef OCTA_ALGORITHM_H
+#define OCTA_ALGORITHM_H
+
+#include "octa/functional.h"
+
+namespace octa {
+}
+
+#endif

octa/functional.h

@@ -0,0 +1,56 @@
+/* Function objects for OctaSTD.
+ *
+ * This file is part of OctaSTD. See COPYING.md for futher information.
+ */
+
+#ifndef OCTA_FUNCTIONAL_H
+#define OCTA_FUNCTIONAL_H
+
+namespace octa {
+#define OCTA_DEFINE_BINARY_OP(name, op, rettype) \
+    template<typename T> struct name { \
+        bool operator()(const T &x, const T &y) const { return x op y; } \
+        struct type { \
+            typedef T first; \
+            typedef T second; \
+            typedef rettype result; \
+        }; \
+    };
+
+    OCTA_DEFINE_BINARY_OP(Less, <, bool)
+    OCTA_DEFINE_BINARY_OP(LessEqual, <=, bool)
+    OCTA_DEFINE_BINARY_OP(Greater, >, bool)
+    OCTA_DEFINE_BINARY_OP(GreaterEqual, >=, bool)
+    OCTA_DEFINE_BINARY_OP(Equal, ==, bool)
+    OCTA_DEFINE_BINARY_OP(NotEqual, !=, bool)
+    OCTA_DEFINE_BINARY_OP(LogicalAnd, &&, bool)
+    OCTA_DEFINE_BINARY_OP(LogicalOr, ||, bool)
+    OCTA_DEFINE_BINARY_OP(Modulus, %, T)
+    OCTA_DEFINE_BINARY_OP(Multiplies, *, T)
+    OCTA_DEFINE_BINARY_OP(Divides, /, T)
+    OCTA_DEFINE_BINARY_OP(Plus, +, T)
+    OCTA_DEFINE_BINARY_OP(Minus, -, T)
+    OCTA_DEFINE_BINARY_OP(BitAnd, &, T)
+    OCTA_DEFINE_BINARY_OP(BitOr, |, T)
+    OCTA_DEFINE_BINARY_OP(BitXor, ^, T)
+
+#undef OCTA_DEFINE_BINARY_OP
+
+    template<typename T> struct LogicalNot {
+        bool operator()(const T &x) const { return !x; }
+        struct type {
+            typedef T argument;
+            typedef bool result;
+        };
+    };
+
+    template<typename T> struct Negate {
+        bool operator()(const T &x) const { return -x; }
+        struct type {
+            typedef T argument;
+            typedef T result;
+        };
+    };
+}
+
+#endif