gistfile1.txt

function getTokens(rawString) {
  // NB: `.filter(Boolean)` removes any falsy items from an array
  return rawString.toLowerCase().split(/[ ,!.";:-]+/).filter(Boolean).sort(); // returns an array of words in the string using all                                                                                        multiples of white space and punctuation as the                                                                                          delimeter, removing any falsy values from array and                                                                                      finally sorting the array members alphabetically 
}

  
function mostFrequentWord(text) {
  var words = getTokens(text);    // parses string into array, filtering out any white space or punctuation
  var wordFrequencies = {};      // creates an object to store unique words and their frequencies
  for (var i = 0; i <= words.length; i++) {    // loops through all words in parsed string array
    if (words[i] in wordFrequencies) {        // checks if current word in array is an existing key in the frequencies object
      wordFrequencies[words[i]]++;           // if it is a key, it updates its value by +1
    }
    else {
      wordFrequencies[words[i]]=1;        // if the word is not already a key, it creates a new key/value pair with the current word and                                              sets its value to 1
    }
  }
  var currentMaxKey = Object.keys(wordFrequencies)[0];   // sets the first word in wordFreq object as the base key with max value for                                                               future comparisons
  var currentMaxCount = wordFrequencies[currentMaxKey];  // sets the the value of the current max key (first word in wordFreq object) as                                                             the base value for max count to use in future comparisons
  
  for (var word in wordFrequencies) {                   // iterates through each key in wordFreq object
    if (wordFrequencies[word] > currentMaxCount) {      // checks if the value of the word on the current iteration is greater than the                                                            current max word value 
      currentMaxKey = word;                             // if it is greater than previous max word count,                                                                                          it updates the max key variable to the current iteration's key (word)
      currentMaxCount = wordFrequencies[word];          // & then it updates the max count variable to the current iteration's                                                                      key (word) value (count)
    }
  }
  return currentMaxKey;        // Finally, the function returns the key/word with the highest count value
}