@Override
    public String format() {
        ConstantParam s = new ConstantParam(functions.get(0).format());
        for (int i = 1; i < functions.size(); i++) {
            s = functions.get(i).apply(s);
        }
        return s.format();
    }
CascadeFunction constructor

@param functions List of functions that cascade functions really need to execute
inlong-sort/sort-common/src/main/java/org/apache/inlong/sort/protocol/transformation/function/CascadeFunctionWrapper.java