CssScale 构造函数

CssScale(
  1. num x,
  2. num y,
  3. [num? z]
)

实现

factory CssScale(num x, num y, [num? z]) {
  if ((y is num) && (x is num) && z == null) {
    return CssScale._create_1(x, y);
  }
  if ((z is num) && (y is num) && (x is num)) {
    return CssScale._create_2(x, y, z);
  }
  throw new ArgumentError("Incorrect number or type of arguments");
}