syntax_data: {"ast_node_type":"other","tokens":[{"end":76,"kind":"keyword","start":0,"text":"impl<I:"}]}
source_snippet: impl<I: Interner, D: rustc_serialize::Decoder> rustc_serialize::Decodable<D>
context_before: #[cfg(feature = "nightly")]
context_after:     for UnsafeBinderInner<I>