syntax_data: {"ast_node_type":"variable","tokens":[{"end":68,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let PseudoCanonicalInput { typing_env, value: trait_ref } = key;
context_before: ) -> Result<&'tcx ImplSource<'tcx, ()>, CodegenObligationError> {
context_after:     // We expect the input to be fully normalized.