syntax_data: {"ast_node_type":"other","tokens":[{"end":81,"kind":"keyword","start":0,"text":"ty::PatternKind::Range"}]}
source_snippet:                                     ty::PatternKind::Range { start, end } => Ok((
context_before:                                 .map(|pat| match *pat {
context_after:                                         extract_const_value(cx, ty, start)