defining data types based on specific conditions within an object {typescript}

Can someone help with implementing conditional function typing in an object?

let obj = {
 function myfunc (input: string): number;
 function myfunc (input: number): string;
 myfunc: function (input: string|number):string|number {
  ...
 }
}

I've been getting syntax errors and have tried various methods, none of which seem to work.

Here are a few examples of my attempts:

let obj = {
 myfunc (input: string): number;
 myfunc (input: number): string;
 myfunc: function (input: string|number):string|number {
  ...
 }
}
let obj = {
 function myfunc (input: string): number;
 function myfunc (input: number): string;
 myfunc: function (input: string|number):string|number {
  ...
 }
}
let obj:{
    function myfunc (input: string) : number;
    function myfunc (input: number) : string;
    myfunc: (input: string|number) => number|string
} = {
    myfunc: function (input: string|number):string|number {
        return ""
    }
}

Answer №1

To resolve the issue, it is important to note that the problem lies in defining the type within the object itself. You can easily fix this by creating a separate interface type for it.

interface NewObj {
  myfunction (input: string): number;
  myfunction (input: number): string;
}


let newObj: NewObj = {
  myfunction: (input: any): any => {
    return 1;
  }
}

Answer №2

An individual in the typescript discord shared a solution with me that has proven to work exceptionally well:

let newObj = {
    myFunction: (() => {
        function myFunction(input: string):number;
        function myFunction(input: number):string;

        function myFunction(input: string|number): number|string {
            let result = input // string|number
            return result
        }

        return myFunction
    })()
}

newObj.myFunction(0) // string
newObj.myFunction("hello") // number

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