How to use

lowerBound

function

in

Array

/**
 * @param {T} object
 * @param {Array.<S>} list
 * @param {function(T,S):number=} comparator
 * @param {boolean=} insertionIndexAfter
 * @return {number}
 * @template T,S
 */
function insertionIndexForObjectInListSortedByFunction(object, list, comparator, insertionIndexAfter)
{
  if (insertionIndexAfter)
    return list.upperBound(object, comparator);
  else
    return list.lowerBound(object, comparator);
}