{"ast_node_type":"other","tokens":[{"end":49,"kind":"keyword","start":0,"text":"#[derive(Debug,"}]}
#[derive(Debug, Decodable, Encodable, PartialEq)]
/// (`${concat("foo", "bar")}`) or adhoc identifiers (`${concat(foo, bar)}`).
pub(crate) enum MetaVarExprConcatElem {