moonbit 的重载

我认为moonbit很有必要完善函数重载

pub fn op_sub(self : Int, that : Double) -> Double {
  self.to_double() - that
}

考虑考虑吧 :melting_face:

[1, 2, 3] * 2 => [2, 4, 6]

pub fn op_mul(self: Array[Int], other: Int) -> Array[Int] {
  // [1, 2, 3] * 2 => [2, 4, 6]
  self.map(fn(x) { x * other })
}

文档里有啊