Swift - 将导入放在文件开头与中间某处是否有任何性能差异？

Question

当我将我的代码安排为时，性能会有缺陷吗，

import Foundation

class Foo { }

import SomethingElse

extension Foo: SomethingElse { }

与将所有导入的模块放在文件开头相比？

import Foundation
import SomethingElse

class Foo { }

extension Foo: SomethingElse { }

Answer 1

没关系，请参阅 here

Most Swift files in your app are order-independent, meaning you can use a type before it is defined, and can even import modules at the bottom of the file (although that is not recommended Swift style.)