swift是否允许没有条件/循环的代码块来减少局部变量范围？

参见英文答案 > How to create local scopes in Swift?                                    5个
在具有块级范围的语言中,我有时会创建任意块,这样我就可以封装局部变量,而不会让它们污染其父级的范围：

func MyFunc() {
  // if statements get block level scope
  if self@L_254_2@meCondition {
    var thisVarShouldntexistElsewhere = true
    self.doSomethingElse(thisVarShouldntexistElsewherE)
  }

  // many languages allow blocks without conditions/loops/etc
  {
    var thisVarShouldntexistElsewhere = false
    self.doSomething(thisVarShouldntexistElsewherE)
  }
}

当我在Swift中执行此操作时,它认为我正在创建一个闭包并且不执行代码.我可以创建它作为一个闭包并立即执行,但这似乎会带来执行开销(不值得为代码清洁).

func MyFunc() {
  // if statements get block level scope
  if self@L_254_2@meCondition {
    var thisVarShouldntexistElsewhere = true
    self.doSomethingElse(thisVarShouldntexistElsewherE)
  }

  // converted to closure
  ({
    var thisVarShouldntexistElsewhere = false
    self.doSomething(thisVarShouldntexistElsewherE)
  })()
}

在Swift中是否支持这样的东西？

func foo() {
    let x = 5

    do {
        let x = 10
        print(X)
    }
}

foo() // prints "10"