syntax_data: {"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     ///   e.g. `1` becomes `tag + "_"`, `2` becomes `tag + "0_"`, etc.
context_before:     /// * `x > 0` is encoded as the `tag` followed by `push_integer_62(x - 1)`
context_after:     fn push_opt_integer_62(&mut self, tag: &str, x: u64) {