syntax_data: {"ast_node_type":"other","tokens":[{"end":81,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // was defined at its invocation (i.e., inside the macros 2.0 definition)
context_before:         // at their invocation. That is, we pretend that the macros 1.0 definition
context_after:         // so that the macros 2.0 definition remains hygienic.