{"ast_node_type":"other","tokens":[{"end":78,"kind":"keyword","start":0,"text":"assert_eq!(size_of::<Option<Option<Option<Option<Option<MyIdx>>>>>>(),"}]}
    assert_eq!(size_of::<Option<Option<Option<Option<Option<MyIdx>>>>>>(), 4);
    // Uses 0xFFFF_FFFF
    // Uses a tag