syntax_data: {"ast_node_type":"other","tokens":[{"end":69,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// the `i32` here is `Invariant.xform(Covariant)`, which results
context_before:     /// respect to its type argument `T`, and hence the variance of
context_after:     /// (again) in `Invariant`.