minor prettification fix when printing out abstract CLOSUREs
minor prettification fix when printing out abstract CLOSUREs

lijunsong/LambdaS5,lijunsong/LambdaS5,brownplt/LambdaS5,logchi/LambdaS5,lijunsong/LambdaS5,logchi/LambdaS5,brownplt/LambdaS5,brownplt/LambdaS5,logchi/LambdaS5