The code provided above is prone to failure. TypeScript may mistakenly infer the return type as `string`, allowing you to use the `charAt` method on it even though the actual type is `number`.
Is there a solution to enhance the code in a way that TypeScript can catch this bug?
function fn(s: number): number
function fn(n: string): string
function fn(arg: any): any { return 0 }
fn("hi").charAt(0)
If you affirm something as true in Typescript, it will trust that you are speaking truthfully.
To uncover a bug, simply eliminate function fn(n: string): string and define only what is verifiably accurate.
The foundational case for method overloading has not been properly defined if we disregard the test scenario. According to https://www.typescriptlang.org/docs/handbook/functions.html#overloads, the base case should be set up as function fn(arg):any, noting the absence of a type on the parameter.
Even with this adjustment, the provided code would still not register as a bug since the fn(n:string):string overload can be inferred from the given argument.
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