However, there is now some burden on the caller in that they need to determine at run - time whether an object implements a particular extension interface.

然而，这样对于调用者产生了额外的负担，他们还要判断对象在运行时是否实现了扩展的接口。

youdao

However, after that, the application exposes an extension interface in a different, higher-level language to make it easy and painless to enhance and customize the interface's behavior.

不过，该应用程序随后会在不同的高级语言中公开扩展接口，以便方便简单地对该接口的行为进行增强和自定义。

youdao

I mean that no changes are needed for extension library interface.

我的意思是现有的扩展库接口不需要更改。

youdao

When computers were the province of corporate programmers and youthful tinkerers he saw their possibilities for illuminating the lives of all of us, seizing on the first gropings by Xerox researchers who developed a primitive mouse and graphical interface, and perceiving in a flash there the chance for an epochal extension of the capabilities of everyone.

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