Item 38: Avoid Repeated Parameters of the Same Type

要点

• Avoid writing functions that take consecutive parameters with the same TypeScript type.
• Refactor functions that take many parameters to take fewer parameters with distinct types, or a single object parameter.
• 避免编写接受连续具有相同 TypeScript 类型的参数的函数。
• 重构接受多个参数的函数，使其接受较少的参数且具有不同的类型，或者将这些参数合并为一个单一的对象参数。

正文

drawRect(25, 50, 75, 100, 1)

💻 playground

---

function drawRect(x: number, y: number, w: number, h: number, opacity: number) {
  // ...
}

💻 playground

---

interface Point {
  x: number
  y: number
}
interface Dimension {
  width: number
  height: number
}
function drawRect(topLeft: Point, size: Dimension, opacity: number) {
  // ...
}

💻 playground

---

drawRect({ x: 25, y: 50 }, { x: 75, y: 100 }, 1.0)
//                        ~
// Argument ... is not assignable to parameter of type 'Dimension'.

💻 playground

---

interface DrawRectParams extends Point, Dimension {
  opacity: number
}
function drawRect(params: DrawRectParams) {
  /* ... */
}

drawRect({ x: 25, y: 50, width: 75, height: 100, opacity: 1.0 })

💻 playground