syntax_data: {"ast_node_type":"other","tokens":[{"end":76,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// current `Binder`. This should not be used if the new value *changes*
context_before:     /// Wraps a `value` in a binder, using the same bound variables as the
context_after:     /// the bound variables. Note: the (old or new) value itself does not