it's a box

box.zig

@@ -0,0 +1,34 @@
+const std = @import("std");
+const stdout = std.io.getStdOut().writer();
+
+fn Box(comptime T: type) type {
+    return struct {
+        value: T,
+    };
+}
+
+const Point = struct {
+    X: i32 = 1,
+    Y: i32 = 2,
+};
+
+pub fn main() !void {
+    var vbox = Box(Point){
+        .value = undefined,
+    };
+    try stdout.print("var box with undefined: {}\n", vbox);
+
+    var vbox2 = Box(Point){
+        .value = Point{},
+    };
+    try stdout.print("var box with explicit defaults: {}\n", vbox2);
+
+    const cbox = Box(Point){
+        .value = undefined,
+    };
+    try stdout.print("const box with undefined: {}\n", cbox);
+
+    try stdout.print("Box literal with undefined: {}\n", Box(Point){
+        .value = undefined,
+    });
+}