Convert array of strings into enum

enumify.ts

type ValuesOfArray<T extends ReadonlyArray<any>> = T[number]

type ToObj<K extends string> = {
    [P in K]: P
}

export const generate = <T extends readonly any[], K extends ValuesOfArray<T>>(
    arr: T,
    start?: number,
    convention?: number
): Readonly<ToObj<K>> => {
    return arr.reduce((acc, elem, idx) => {
        return {
            ...acc,
            [elem]: idx + (start || 0) + (convention || 0)
        }
    }, {})
}