syntax_data: {"ast_node_type":"variable","tokens":[{"end":46,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let byte_strs = FxIndexSet::from_iter(
context_before:     fn prefill(init: &[&'static str], extra: &[&'static str]) -> Self {
context_after:             init.iter().copied().chain(extra.iter().copied()).map(|str| str.as_bytes()),