Fix bad error message in unify (#3801)
Fix bad error message in unify (#3801)


danking/hail,cseed/hail,danking/hail,danking/hail,hail-is/hail,hail-is/hail,hail-is/hail,danking/hail,cseed/hail,cseed/hail,danking/hail,danking/hail,cseed/hail,hail-is/hail,cseed/hail,cseed/hail,danking/hail,danking/hail,cseed/hail,hail-is/hail,hail-is/hail,hail-is/hail,cseed/hail,hail-is/hail