syntax_data: {"ast_node_type":"other","tokens":[{"end":48,"kind":"keyword","start":0,"text":"debug!(\"source_len=`{:?}`\","}]}
source_snippet:         debug!("source_len=`{:?}`", source_len);
context_before:         let source_len = local_begin.sf.source_len.to_usize();
context_after:         // Ensure indexes are also not malformed.