在DXL脚本中，除了字符串数组的每个元素的第一个字母外，如何在每个大写字母中插入空格字符？

string[] insertSpace(string[] arr) {
    for (int i = 0; i < length(arr); i++) {
        string element = arr[i];
        string firstLetter = substr(element, 0, 1);
        string restLetters = substr(element, 1);
        string upperCaseFirstLetter = upper(firstLetter);
        string spacedElement = upperCaseFirstLetter;
        
        // 使用正则表达式匹配大写字母，并在匹配到的大写字母前插入空格字符
        string pattern = "[A-Z]";
        string replacement = " $0";
        spacedElement = regex_replace(spacedElement, pattern, replacement);
        
        arr[i] = spacedElement + restLetters;
    }
    
    return arr;
}

string[] inputArr = {"HelloWorld", "CloudComputing", "BigData"};
string[] outputArr = insertSpace(inputArr);
print outputArr;

{"Hello World", "Cloud Computing", "Big Data"}