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export type ReduceCallbackFunction<ArrOf, ReduceTo> = (    previousValue: ReduceTo,    currentValue: ArrOf,    currentIndex: number,    array: readonly ArrOf[]) => ReduceTo;
export type ReduceArguments<ArrOf, ReduceTo> = [ReduceCallbackFunction<ArrOf, ReduceTo>, ReduceTo];
export function toReduceArguments<ArrOf, ReduceTo, Params extends any[]>(    arrOp: (arr: readonly ArrOf[], ...params: Params) => ReduceTo,    ...params: Params): ReduceArguments<ArrOf, ReduceTo> {
    let outWrap: [ReduceTo] | [] = [];
    const reduceCallbackFunction: ReduceCallbackFunction<ArrOf, ReduceTo> = (...[, , , array]) => {
        let out: ReduceTo;
        if (outWrap.length === 1) {            out = outWrap[0];        } else {            out = arrOp(array, ...params);            outWrap = [out];        }
        return out;
    };
    return [        reduceCallbackFunction,        arrOp([], ...params)    ];
}