Typing.ts

​
type FunctionPropertyNames<T> = { [K in keyof T]: T[K] extends Function ? K : never }[keyof T];
type rule<T> = {[key in FunctionPropertyNames<T>]?: T[key] extends (args: infer U) => void ? U : never};
​
class rules {
    ruleOne(args: {first: string, second: number}) { }
    
}
​
function ruleTwo(args: {first: number}) { }  
​
let test: rule<rules & {ruleTwo: typeof ruleTwo}> = {
    ruleOne: { first: '', second: 3 },
    ruleTwo: { first: 2 }
}