syntax_data: {"ast_node_type":"other","tokens":[{"end":42,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                     //   - `Foo<T>: Trait`
context_before:                     //     - `WF(Foo<T>)`
context_after:                     // In this case, the innermost `WF(Foo<T>)` should return