getFunctionValue = (value, target, index, total, store) => {
  if (isFnc(value)) {
    const func = () => {
      const computed = /** @type {Function} */(value)(target, index, total);
      // Fallback to 0 if the function returns undefined / NaN / null / false / 0
      return !isNaN(+computed) ? +computed : computed || 0;
    };
    if (store) {
      store.func = func;
    }
    return func();
  } else {
    return value;
  }
}
@param  {TweenPropValue} value
@param  {Target} target
@param  {Number} index
@param  {Number} total
@param  {Object} [store]
@return {any}