• d-bugmail puremagic.com (35/35) Oct 25 2021 https://issues.dlang.org/show_bug.cgi?id=22434

d-bugmail puremagic.com writes:

https://issues.dlang.org/show_bug.cgi?id=22434

          Issue ID: 22434
           Summary: Nested struct or not nested struct?
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: stanislav.blinov gmail.com

struct Storage(T) {
    T[1] items;

    this(T[] arr) {  // Error: field `items` must be initialized in
constructor, because it is nested struct
        /* ... */
    }
}

void test() {
    struct Cat {
        ~this() {} // nested
    }
    struct Box {
        Cat cat;
    }
    //static assert(__traits(isNested, Box)); // would fail if uncommented

    Storage!Box storage;
}

---

Cat is nested. Box contains Cat, has no explicitly defined methods, but does
have __xdtor due to Cat. Does not appear as a nested struct through __traits,
but stumps Storage's ctor "because it is nested struct".

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