E3010

E3010#

只有带标签参数才可以有默认值。

错误示例#

pub fn greet(name : String = "World") -> Unit {
  //                       ^ Error: Only labelled arguments can have default value.
  println("Hello, " + name + "!")
}

建议#

Use an optional argument with ? if you want to provide a default value:

///|
pub fn greet(name? : String = "World") -> Unit {
  println("Hello, " + name + "!")
}

或者如果你想保持它为一个位置参数,移除默认值:

///|
pub fn greet_without_default(name : String) -> Unit {
  println("Hello, " + name + "!")
}