{"ast_node_type":"other","tokens":[{"end":68,"kind":"keyword","start":0,"text":"let_span.shrink_to_hi().to(val_span.shrink_to_lo()),"}]}
                let_span.shrink_to_hi().to(val_span.shrink_to_lo()),
            err.span_suggestion_verbose(
                "you might have meant to use `:` for type annotation",