private CompositeItem buildWeakAnd(OperatorNode<ExpressionOperator> spec) {
        WeakAndItem weakAnd = new WeakAndItem();
        Integer targetNumHits = getAnnotation(spec, TARGET_HITS,
                Integer.class, null, "desired minimum hits to produce");
        if (targetNumHits == null) {
            targetNumHits = getAnnotation(spec, TARGET_NUM_HITS,
                Integer.class, null, "desired minimum hits to produce");
        }
        if (targetNumHits != null) {
            weakAnd.setN(targetNumHits);
        }
        return convertVarArgs(spec, 1, weakAnd);
    }
Build a "pure" not, without any positive terms.
container-search/src/main/java/com/yahoo/search/yql/YqlParser.java