How to use the vuelidate/lib/validators.helpers.withParams function in vuelidate

// excerpt from vue-class-component/src/declarations.ts
type VueClass = { new(...args: any[]): V & Vue } & typeof Vue
// excerpt from vue-class-component/src/index.ts
function Component(options: ComponentOptions | VueClass): any {
    return null; // mocked
}

const mustBeCool: CustomRule = (value: string) => value.indexOf('cool') >= 0

const mustBeCool2: CustomRule = (value: string) => !helpers.req(value) || value.indexOf('cool') >= 0

const contains = (param: string): CustomRule =>
    (value: string) => !helpers.req(value) || value.indexOf(param) >= 0

const mustBeCool3 = helpers.withParams(
    { type: 'mustBeCool3' },
    (value: any) => !helpers.req(value) || value.indexOf('cool') >= 0
)

const mustBeCool3Result: boolean = mustBeCool3(50)

const mustBeCool4 = helpers.regex('mustBeCool4', /^.*cool.*$/)

const mustBeSame = (reference: string) => helpers.withParams(
    { type: 'mustBeSame' },
    (value: any, parentVm?: Vue) =>
        value === helpers.ref(reference, self, parentVm)
)

const mustHaveLength = (minLen: number) => helpers.withParams(
    { type: 'mustHaveLength' },

const mustBeSame = (reference: string) => helpers.withParams(
    { type: 'mustBeSame' },
    (value: any, parentVm?: Vue) =>
        value === helpers.ref(reference, self, parentVm)
)