syntax_data: {"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"for"}]}
source_snippet:         for (idx, cache_entry) in self.line_cache.iter().enumerate() {
context_before:     fn cache_entry_index(&self, pos: BytePos) -> isize {
context_after:             if cache_entry.line.contains(&pos) {