Because the runtime cannot tell a List from a List (at runtime, they're both just Lists), constructing variables whose type is identified by a generic type parameter is problematic.

因为运行时不能区分List和List(运行时都是List)，用泛型类型参数标识类型的变量的构造就成了问题。

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A generic procedure can use its type parameters in its normal parameter list, in its return type if it has one, and in its procedure code.

泛型程序可以在一般参数清单、传回型别(如果有的话)和程序程序码中使用自己的型别参数。

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