Challenge analyze a most frequent word program.txt

function getTokens(rawString) {
  // NB: `.filter(Boolean)` removes any falsy items from an array
  return rawString.toLowerCase().split(/[ ,!.";:-]+/).filter(Boolean).sort();
}

function mostFrequentWord(text) {
  // Turn the text into an array of tokens
  let words = getTokens(text);
  // Create an empty object to hold data about each word.
  let wordFrequencies = {};
  // Loop through each token in words array.
  for (let i = 0; i <= words.length; i++) {
    // Increment value of word in wordFrequencies if current word is already in wordFrequencies.
    if (words[i] in wordFrequencies) {
      wordFrequencies[words[i]]++;
    // Add key and value for word to be added to wordFrequences object.
    } else {
      wordFrequencies[words[i]] = 1;
    }
  }
  // Set default values for testing max value.
  let currentMaxKey = Object.keys(wordFrequencies)[0];
  let currentMaxCount = wordFrequencies[currentMaxKey];

  // Iterate wordFrequencies and update currentMax values if logic satisfied
  for (let word in wordFrequencies) {
    if (wordFrequencies[word] > currentMaxCount) {
      currentMaxKey = word;
      currentMaxCount = wordFrequencies[word];
    }
  }
  return currentMaxKey;
}