syntax_data: {"ast_node_type":"variable","tokens":[{"end":61,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let mut child = self.places[rhs].first_child;
context_before:                 // Conversely, mirror children from `rhs` in `lhs`.
context_after:                 while let Some(rhs_child) = child {