syntax_data: {"ast_node_type":"other","tokens":[{"end":10,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         //
context_before:         // macros 2.0 expansion, i.e., a macros 1.0 invocation is in a macros 2.0 definition.
context_after:         // In this case, the tokens from the macros 1.0 definition inherit the hygiene