syntax_data: {"ast_node_type":"other","tokens":[{"end":42,"kind":"keyword","start":0,"text":"from:"}]}
source_snippet:                 from: prefix.len() as u64,
context_before:             let subslice = place.clone_project(PlaceElem::Subslice {
context_after:                 to: if exact_size { min_length - suffix_len } else { suffix_len },