syntax_data: {"ast_node_type":"other","tokens":[{"end":50,"kind":"keyword","start":0,"text":"Err(OverflowError::Canonical)"}]}
source_snippet:                 Err(OverflowError::Canonical) => {
context_before:                 Ok(_) => Ok(None),
context_after:                     Err(SelectionError::Overflow(OverflowError::Canonical))