syntax_data: {"ast_node_type":"other","tokens":[{"end":69,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                     // `value` is not contained in the testing range,
context_before:                 if !range.contains(value, self.tcx, self.typing_env())? {
context_after:                     // so `value` can be matched only if this test fails.