Inheritance of Generic Types in TypeScript

Could someone assist me in understanding what is incorrect with the code snippet provided here? I am still learning Typescript.

interface ICalcValue {

    readonly IsNumber: boolean;

    readonly IsString: boolean;

}

interface ICalcValue<T> extends ICalcValue {

    readonly T Value;

}

Answer №1

In contrast to languages like C#, TypeScript does not allow for having two types that differ only by type parameters. To work around this, it is necessary to use distinct names for the interfaces and correct any other minor syntax errors:

interface ICalcValueBase {

    readonly IsNumber: boolean;

    readonly IsString: boolean;

}

interface ICalcValue<T> extends ICalcValueBase {

    readonly Value: T;

}

play

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