Initial data commit

Task/Compound-data-type/D/compound-data-type.d

@@ -0,0 +1,47 @@
+void main() {
+    // A normal POD struct
+    // (if it's nested and it's not static then it has a hidden
+    // field that points to the enclosing function):
+    static struct Point {
+        int x, y;
+    }
+
+    auto p1 = Point(10, 20);
+
+    // It can also be parametrized on the coordinate type:
+    static struct Pair(T) {
+        T x, y;
+    }
+
+    // A pair with integer coordinates:
+    auto p2 = Pair!int(3, 5);
+
+    // A pair with floating point coordinates:
+    auto p3 = Pair!double(3, 5);
+
+    // Classes (static inner):
+    static class PointClass {
+        int x, y;
+        this(int x_, int y_) {
+            this.x = x_;
+            this.y = y_;
+        }
+    }
+
+    auto p4 = new PointClass(1, 2);
+
+    // There are also library-defined tuples:
+    import std.typecons;
+
+    alias Tuple!(int,"x", int,"y") PointXY;
+
+    auto p5 = PointXY(3, 5);
+
+    // And even built-in "type tuples":
+    import std.typetuple;
+
+    alias TypeTuple!(int, 5) p6;
+
+    static assert(is(p6[0] == int));
+    static assert(p6[1] == 5);
+}