     ".private" ?tail drop ".private" append ;
 
 : coverage-words ( string -- words )
-    vocab-words [ { [ primitive? not ] [ symbol? not ] [ predicate? not ] } 1&& ] filter ;
+    vocab-words [
+        {
+            [ primitive? not ]
+            [ symbol? not ]
+            [ predicate? not ]
+        } 1&&
+    ] filter ;
 
 PRIVATE>
 

M: string coverage.
    [ coverage. ] each-word ;

: pair-coverage. ( word quots -- )
    dup empty? [
        2drop
    ] [
        [ name>> ":" append print ]
        [ [ "    " write . ] each ] bi*
    ] if ;

M: word coverage.
    dup coverage pair-coverage. ;

    [ dup coverage 2array ] map-words ;

M: word coverage ( word -- seq )
    "coverage" word-prop
    [ drop executed?>> ] assoc-reject values ;

GENERIC: coverage. ( object -- )
