syntax_data: {"ast_node_type":"variable","tokens":[{"end":45,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let mut hasher = StableHasher::new();
context_before:     fn hash_expn(&self, ctx: &mut impl HashStableContext) -> Hash64 {
context_after:         self.hash_stable(ctx, &mut hasher);