如何确保alphaStr不会生成空字符串？

let alphaStr = 'default'; // 初始化为非空字符串

let potentialStr = ''; // 假设这是从某处获取的字符串
let alphaStr = potentialStr || 'default'; // 如果potentialStr为空，则使用'default'

function getAlphaStr() {
    let str = someLogicToGetStr(); // 假设这是获取字符串的逻辑
    return str || 'default'; // 如果str为空，则返回'default'
}

let alphaStr = getAlpha_str();

alphaStr = some_function_that_returns_str()
assert alphaStr != '', "alphaStr should not be an empty string" # Python中的断言

String alphaStr = someMethodThatReturnsStr();
if (alphaStr.isEmpty()) {
    throw new IllegalArgumentException("alphaStr should not be an empty string");
}