syntax_data: {"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"///"}]}
source_snippet: /// enclosing function, we couldn't name this lifetime `'b`. Note that
context_before: /// `do()`. If we just had the lifetime/type parameters from the
context_after: /// there can also be lifetimes in the types of the upvars themselves,