syntax_data: {"ast_node_type":"variable","tokens":[{"end":32,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let maybe_transmutable =
context_before:         let mut transmute_env = rustc_transmute::TransmuteTypeEnv::new(self.infcx.tcx);
context_after:             transmute_env.is_transmutable(rustc_transmute::Types { dst, src }, assume);