Struct

    pub const Struct = struct {
        is_tuple: bool,
        layout: ContainerLayout,
        /// Always `null` if `layout != .@"packed"`.
        backing_integer: ?type,

        field_names: []const [:0]const u8,
        /// Guaranteed to have the same length as `field_names`.
        field_types: []const type,
        /// Guaranteed to have the same length as `field_names`.
        field_attrs: []const FieldAttributes,

        decl_names: []const [:0]const u8,

        pub const FieldAttributes = struct {
            @"comptime": bool = false,
            /// `null` means the field alignment is not explicitly specified. The field will still
            /// be aligned to at least `@alignOf` the field type.
            @"align": ?usize = null,
            /// The type of the default value is the type of this struct field. However, that type
            /// is not known here, so we use a type-erased pointer instead, which must be cast to
            /// a pointer to the field type.
            ///
            /// See also: `defaultValue`.
            default_value_ptr: ?*const anyopaque = null,

            /// Loads the field's default value from `default_value_ptr`.
            /// `FieldType` must exactly match the corresponding element of `Struct.field_types`.
            /// Returns `null` if the field has no default value.
            pub inline fn defaultValue(comptime attrs: FieldAttributes, comptime FieldType: type) ?FieldType {
                const dp: *const FieldType = @ptrCast(@alignCast(attrs.default_value_ptr orelse return null));
                return dp.*;
            }
        };
    }