javascript是弱类型语言，一个函数参数可以接收不同类型的变量作为它的该参数。
如：noticeEstateSales的week参数可以是空，数字类型（4），字符串（‘登记’， ‘4’）类型。
这在强类型语言（如：Object c,java）中是无法理解的。
当然弱类型语言好处也有，就是因为它不太讲究，健壮性很高，不用crash。缺点是：当出现问题时，不容易定位。如：一个地方调用是正常的，另一个地方调用就有可能是异常的。
下面是一个例子函数：
erp_notice_saler.noticeEstateSales = async function (week, estate_id) { logger.debug('noticeEstateSales timer: start'); let wordsMap = { '1': '快', '2': '上', '3': '上', '4': '快来', '登记': '您', }; let words = wordsMap[week]; }
传递不同的参数调用：
const date = new Date(); const week = date.getDay(); erp_notice_saler.noticeEstateSales(week); erp_notice_saler.noticeEstateSales(4); erp_notice_saler.noticeEstateSales(5); erp_notice_saler.noticeEstateSales('4');
打印日志：
[2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: week: 1 [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: wordsMap[week] 快来更新预计开盘信息，能同时获得积分和展位，先到先审先得！~ week: 1 [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: start [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: week: 4 [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: wordsMap[week] 快来 week: 4 [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: start [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: week: 5 [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: wordsMap[week] undefined week: 5 [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: start [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: week: 4 [2024-05-13T12:00:25.151] [DEBUG] app - noticeEstateSales timer: wordsMap[week] 快来 week: 4
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