syntax_data: {"ast_node_type":"variable","tokens":[{"end":48,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let Binder { value, bound_vars } = self;
context_before:     pub fn transpose(self) -> Option<Binder<I, T>> {
context_after:         value.map(|value| Binder { value, bound_vars })