syntax_data: {"ast_node_type":"other","tokens":[{"end":79,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// needs to be recorded. A panic will be triggered if that doesn't happen.
context_before:     /// Note: when self-profiling with costly event arguments, at least one argument
context_after:     fn record_arg_with_span<A>(&mut self, source_map: &SourceMap, event_arg: A, span: crate::Span)