Force generics implements property in TypeScript (constrains on generics)

Question

I want to force that generic implements property in TypeScript.
My current code is:

interface IEventHandler<TArgs>

{

    (args: TArgs): void

}





interface ISubscribable<THandlerType>

{ 

    bind(fn: THandlerType): void;



    unbind(fn: THandlerType): void;

}



interface IEvent<TArgs> extends ISubscribable<IEventHandler<TArgs>>

{

}

Something like

interface IEventHandler<TArgs> where TArgs : has_property_sender

. I know where does not exists for TypeScript, so maybe I can get a workaround with another interface?

Is this possible in TypeScript?

Edited:

Code if it helps someone else. I don't know if it can be optimized.

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Answer 1

You can use constraints (section "Generic Constraints") in Typescript, e.g.:

interface has_property_sender {
    sender: Object;
}

interface MyArgs extends has_property_sender {
    property: Object;
}

interface IEventHandler<TArgs extends has_property_sender>
{
    (args: TArgs): void
}

Force generics implements property in TypeScript (constrains on generics)

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