{"ast_node_type":"other","tokens":[{"end":91,"kind":"keyword","start":0,"text":"//"}]}
        // straight-forward (`TagEncoding::Direct`) or with a niche (`TagEncoding::Niche`).
        // We use "tag" to refer to how the discriminant is encoded in memory, which can be either
        let (tag_scalar_layout, tag_encoding, tag_field) = match op.layout().variants {