{"ast_node_type":"variable","tokens":[{"end":80,"kind":"keyword","start":0,"text":"let"}]}
                let index_lane = index.value_lane(fx, lane_idx).load_scalar(fx);
                let src_lane = src.value_lane(fx, lane_idx).load_scalar(fx);
                let mask_lane = mask.value_lane(fx, lane_idx).load_scalar(fx);