18 lines
664 B
JavaScript
18 lines
664 B
JavaScript
// supporting `this` type in statics
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class A {
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static make(): this { // factory method, whose return type `this` (still)
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// describes instances of A or subclasses of A: the
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// meaning of the `this` type is not changed simply by
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// switching into a static context
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return new this; // but in a static context, the value `this` is bound to
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// the class, instead of instances of the class
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}
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}
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class B extends A { } // inherits statics method too, with `this` bound to the class
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(A.make(): A); // OK
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(B.make(): B); // OK
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(B.make(): A); // OK
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(A.make(): B); // error
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