src/main/java/org/organicdesign/fp/collections/RrbTree.java
private static StringBuilder showSubNodes(StringBuilder sB, Object[] items, int nextIndent) {
        boolean isFirst = true;
        for (Object n : items) {
            if (isFirst) {
                isFirst = false;
            } else {
//                sB.append(" ");
                if (items[0] instanceof Leaf) {
                    sB.append(" ");
                } else {
                    sB.append("\n").append(indentSpace(nextIndent));
                }
            }
            sB.append(((Node) n).indentedStr(nextIndent));
        }
        return sB;
    }
private static StringBuilder showSubNodes(StringBuilder sB, Object[] items, int nextIndent) {
        boolean isFirst = true;
        for (Object n : items) {
            if (isFirst) {
                isFirst = false;
            } else {
//                sB.append(" ");
                if (items[0] instanceof Leaf) {
                    sB.append(" ");
                } else {
                    sB.append("\n").append(indentSpace(nextIndent));
                }
            }
            sB.append(((Node) n).indentedStr(nextIndent));
        }
        return sB;
    }
=============================== Debugging and pretty-printing ===============================