syntax_data: {"ast_node_type":"other","tokens":[{"end":78,"kind":"keyword","start":0,"text":"[single]"}]}
source_snippet:                         [single] if body.expr.is_none() => match single.kind {
context_before:                         },
context_after:                             hir::StmtKind::Expr(expr) | hir::StmtKind::Semi(expr) => expr,