index.ts

type CompareResult = number
type CompareFunction<T> = (a: T, b: T) => CompareResult

export function compareStrings(sA: string, sB: string) {
    return sA > sB ? 1 : sA < sB ? -1 : 0
}

export function compareNumbers(sA: number, sB: number) {
    return sA - sB
}

export function reverse(r: CompareResult) {
    return -r
}

export function compareStringsCaseInsensitive(sA: string, sB: string) {
    return sA.localeCompare(sB, undefined, {
        sensitivity: 'base',
    }) as CompareResult
}

export function sortFunction<T>(
    gen: (a: T, b: T) => IterableIterator<CompareResult>
): CompareFunction<T> {
    return (a: T, b: T) => {
        for (let comp of gen(a, b)) {
            if (comp) {
                return comp
            }
        }

        return 0
    }
}