scala传参有两种方式
第一种:变量:类型
val logEnable = false
def log(msg: String) =
if (logEnable) println(msg)
val MSG = "programing is running"
# 程序会在1 / 0这个报空指针
# java.lang.ArithmeticException: / by zero
log(MSG + 1 / 0)
第二种:变量 => 类型
val logEnable = false
# 不报异常,也没输出
def log(msg: String) =
if (logEnable) println(msg)
val MSG = "programing is running"
# 1/0在log函数里计算,所以这里没报异常
log(MSG + 1 / 0)
在实际使用中,根据具体需求来设计使用吧。