presto-main/src/main/java/io/prestosql/sql/planner/planprinter/TextRenderer.java/Indent/Indent
class Indent:        private Indent(String firstLinePrefix, String nextLinesPrefix, boolean hasChildren)
        {
            this.firstLinePrefix = firstLinePrefix;
            this.nextLinesPrefix = nextLinesPrefix;
            this.hasChildren = hasChildren;
        }