{"ast_node_type":"variable","tokens":[{"end":43,"kind":"keyword","start":0,"text":"let"}]}
    let InferArg { hir_id, span: _ } = inf;
pub fn walk_inf<'v, V: Visitor<'v>>(visitor: &mut V, inf: &'v InferArg) -> V::Result {
    visitor.visit_id(*hir_id)