HarmonyOS Next 原生应用开发-从TS到ArkTS的适配规则（四）

class C {
  #foo: number = 42
}

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class C {
  private foo: number = 42
}

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let X: string
type X = number[] // 类型的别名与变量同名

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let X: string
type T = number[] // 为避免名称冲突，此处不允许使用X

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function f(shouldInitialize: boolean) {
  if (shouldInitialize) {
     var x = 'b';
  }
  return x;
}

console.log(f(true));  // b
console.log(f(false)); // undefined

let upperLet = 0;
{
  var scopedVar = 0;
  let scopedLet = 0;
  upperLet = 5;
}
scopedVar = 5; // 可见
scopedLet = 5; // 编译时错误

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function f(shouldInitialize: boolean): string {
  let x: string = 'a';
  if (shouldInitialize) {
    x = 'b';
  }
  return x;
}

console.log(f(true));  // b
console.log(f(false)); // a

let upperLet = 0;
let scopedVar = 0;
{
  let scopedLet = 0;
  upperLet = 5;
}
scopedVar = 5;
scopedLet = 5; //编译时错误

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