In order for the argument to be valid, it is

Transitioning to Typescript has brought me immense joy for various reasons.

While exploring its benefits, I encountered a challenge related to verifying if an argument passed to a function extends another class.

Here is an example scenario:

class Foo {
    public $xyz
}

class Bar {
    constructor(model: extends Foo)
}

class Baz extends Foo {}

Multiple classes can extend foo, not just Baz, but they all share the same properties. To ensure that the class passed to the model parameter of the Bar constructor correctly extends Foo, how can this be accomplished?

(excuse the rough pseudo-code provided)

If my approach is flawed, I am open to suggestions on how to overcome this issue.

typescript

Answer №1

constuctor(parameter: Bar)

This code snippet indicates that the parameter parameter is expected to be of type Bar or a subclass of Bar.

The keyword extends is specifically used in type declarations to show that one type inherits from another.

For more information, refer to the Classes documentation.

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