syntax_data: {"ast_node_type":"function","tokens":[{"end":31,"kind":"keyword","start":0,"text":"fn"}]}
source_snippet:     fn to_json(&self) -> Json {
context_before: impl<A: ToJson> ToJson for Vec<A> {
context_after:         Json::Array(self.iter().map(|elt| elt.to_json()).collect())