blocks|key|2646369|text|更改函数的签名，以便泛型类型T扩展类型object，在Typescript+2.2中引入。使用以下语法-+<T+extends+object>|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2646370|function+create<T+extends+object>(prototype:+T,+pojo:+Object):+T+{
++++...
++++return+Object.create(prototype,+descriptors)+as+T;
}|code-block|syntax|javascript|2646371|entityMap^0|E|1|J|6|1H|I|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|U|8|@]|D|@]|E|$]]]|L|$]]

Change signature of the function, so that generic type <code>T</code> extends type <code>object</code>, introduced in Typescript 2.2. Use this syntax - <code>&lt;T extends object&gt;</code>:

<pre><code>function create&lt;T extends object&gt;(prototype: T, pojo: Object): T {
 ...
 return Object.create(prototype, descriptors) as T;
}
</code></pre>

blocks|key|107981|text|TypeScript+2.2中更改了Object.create的签名。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|107982|在TypeScript+2.2之前，Object.create的类型定义是：|107983|create(o:+any,+properties:+PropertyDescriptorMap):+any;|code-block|syntax|javascript|107984|但正如您所指出的，TypeScript+2.2+introduced+object类型：|107985|107986|+TypeScript没有表示非基元类型的类型，即任何不是number+%7C+string+%7C+boolean+%7C+symbol+%7C+null+%7C+undefined的类型。输入新的对象类型。|blockquote|107987|107988|使用对象类型，可以更好地表示像Object.create这样的API。|107989|107990|Object.create的类型定义已更改为：|107991|create(o:+object,+properties:+PropertyDescriptorMap):+any;|107992|因此，您示例中的泛型类型T不能赋值给object，除非编译器被告知T扩展了object。|107993|在2.2版之前，编译器不会捕获这样的错误：|107994|Object.create(1,+{});|107995|现在编译器会报错：|107996|“%251”类型的|107997|参数不能赋值给“object”类型的参数。|107998|107999|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/Microsoft/TypeScript/wiki/What%2527s-new-in-TypeScript#object-type^0|I|D|0|I|D|0|0|Z|6|9|P|0|0|0|T|6|12|6|1B|7|1L|6|1U|4|21|9|0|0|0|0|0|D|0|0|C|1|I|6|X|1|11|6|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|1L|8|@$9|1M|A|1N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1O|8|@$9|1P|A|1Q|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|1R|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|1S|8|@$9|1T|A|1U|B|C]]|D|@$9|1V|A|1W|1|1X]]|E|$]]|$1|O|3|-4|5|6|7|1Y|8|@]|D|@]|E|$]]|$1|P|3|Q|5|R|7|1Z|8|@$9|20|A|21|B|C]|$9|22|A|23|B|C]|$9|24|A|25|B|C]|$9|26|A|27|B|C]|$9|28|A|29|B|C]|$9|2A|A|2B|B|C]]|D|@]|E|$]]|$1|S|3|-4|5|6|7|2C|8|@]|D|@]|E|$]]|$1|T|3|U|5|6|7|2D|8|@]|D|@]|E|$]]|$1|V|3|-4|5|6|7|2E|8|@]|D|@]|E|$]]|$1|W|3|X|5|6|7|2F|8|@$9|2G|A|2H|B|C]]|D|@]|E|$]]|$1|Y|3|Z|5|J|7|2I|8|@]|D|@]|E|$K|L]]|$1|10|3|11|5|6|7|2J|8|@$9|2K|A|2L|B|C]|$9|2M|A|2N|B|C]|$9|2O|A|2P|B|C]|$9|2Q|A|2R|B|C]]|D|@]|E|$]]|$1|12|3|13|5|6|7|2S|8|@]|D|@]|E|$]]|$1|14|3|15|5|J|7|2T|8|@]|D|@]|E|$K|L]]|$1|16|3|17|5|6|7|2U|8|@]|D|@]|E|$]]|$1|18|3|19|5|6|7|2V|8|@]|D|@]|E|$]]|$1|1A|3|1B|5|R|7|2W|8|@]|D|@]|E|$]]|$1|1C|3|-4|5|6|7|2X|8|@]|D|@]|E|$]]|$1|1D|3|-4|5|6|7|2Y|8|@]|D|@]|E|$]]]|1E|$1F|$5|1G|1H|1I|E|$1J|1K]]]]

The signature for <code>Object.create</code> was changed in TypeScript 2.2.
Prior to TypeScript 2.2, the type definition for <code>Object.create</code> was:
<pre><code>create(o: any, properties: PropertyDescriptorMap): any;
</code></pre>
But as you point out, <a href="https://github.com/Microsoft/TypeScript/wiki/What%27s-new-in-TypeScript#object-type" rel="noreferrer">TypeScript 2.2 introduced</a> the <code>object</code> type:
<blockquote>
TypeScript did not have a type that represents the non-primitive type, i.e. any thing that is not <code>number</code> | <code>string</code> | <code>boolean</code> | <code>symbol</code> | <code>null</code> | <code>undefined</code>. Enter the new object type.
With object type, APIs like Object.create can be better represented.
</blockquote>
The type definition for <code>Object.create</code> was changed to:
<pre><code>create(o: object, properties: PropertyDescriptorMap): any;
</code></pre>
So the generic type <code>T</code> in your example is not assignable to <code>object</code> unless the compiler is told that <code>T</code> extends <code>object</code>.
Prior to version 2.2 the compiler would not catch an error like this:
<pre><code>Object.create(1, {});
</code></pre>
Now the compiler will complain:
<blockquote>
Argument of type '1' is not assignable to parameter of type 'object'.
</blockquote>

The code below was working fine with TypeScript 2.1.6:

<pre><code>function create&lt;T&gt;(prototype: T, pojo: Object): T {
 // ...
 return Object.create(prototype, descriptors) as T;
}
</code></pre>

After updating to TypeScript 2.2.1, I am getting the following error:

<blockquote>
 error TS2345: Argument of type 'T' is not assignable to parameter of
 type 'object'.
</blockquote>

error TS2345: Argument of type 'T' is not assignable to parameter of type 'object'

TypeScript

编译器

下面的代码在TypeScript 2.1.6上运行良好：function create<T>(prototype: T, pojo: Object): T { // ... return Object.create(prototype, descriptors) as T;}更新到TypeScript 2....

问错误对象：'T‘类型的参数不能赋值给’TS2345‘类型的参数
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