syntax_data: {"ast_node_type":"other","tokens":[{"end":80,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                             // Okay, let's imagine we have two different stacks:
context_before:                         if let Some(stack) = previous_stack.head {
context_after:                             //   `T: NonAutoTrait -> WF(T) -> T: NonAutoTrait`