So you're implementing this black box, and if its purpose in life is to actually return a value, you have to tell the compiler what kind of value to expect, and this is going to have ripple effects.

你在实现这个黑盒子，如果它的目的是,返回一个值，你必须告诉编译器你期望的是什么类型的值，这个将是一个连锁反应。

哈佛公开课 - 计算机科学课程节选

All these things have ripple effects.

所有我们所做的都会产生连锁反应。

普林斯顿公开课 - 人性课程节选