Imagine we have a generic interface:
export interface IKeyValue<K, V> {
key: K;
value: V;
}
Now, our goal is to define a variable or field and restrict the types that can be used as K and V:
public items: IKeyValue<K extends Type1, V extends Type2>[];
This code does not compile.
I am working with TypeScript 2.6.
How can we accomplish this in TypeScript?
The reason for this is that you are offering an example rather than a definition.
public items: IKeyValue<Type1, Type2>[];
This is the correct syntax to use.
If you want to constrain the definition (interface), you can use the 'extends' keyword:
export interface IKeyValue<K extends Type1, V extends Type2> {
key: K;
value: V;
}
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