syntax_data: {"ast_node_type":"other","tokens":[{"end":77,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // the macro input with spans produced by the macro (`Span::*_site`).
context_before:         // Context mismatches usually happen when procedural macros combine spans copied from
context_after:         // In that case we consider the combined span to be produced by the macro and return