I need to make a function type that tells me what the type must be for the second value based on the first value
type BType = number | string | array
enum AEnum = { number = "number" , string : "string" , array : "array"}
const fc = (a : AEnum , b : BType)=>{
//...
}
What I need is that when a = AEnum.array, then b must be array, or an error should be shown
How can I make something like this ??
CodePudding user response：
Just overload the function !
type BType = number | string | []
enum AEnum { number = "number", string = "string", array = "array" }
function foo(a: AEnum.number, b: number): unknown;
function foo(a: AEnum.string, b: string): unknown;
function foo(a: AEnum.array, b: []): unknown;
function foo(a: AEnum, b: BType): unknown {
return void;
}