prettify.js

function prettify(document){
    // Turns an array of words into lowercase and removes stopwords
    const stopwords = ["a", "share", "linkthese", "about", "above", "after", "again", "against", "all", "am", "an", "and", "any","", "are","aren't","as","at","be","because","been","before","being","below","between","both","but","by","can't","cannot","could","couldn't","did","didn't","do","does","doesn't","doing","don't","down","during","each","few","for","from","further","had","hadn't","has","hasn't","have","haven't","having","he","he'd","he'll","he's","her","here","here's","hers","herself","him","himself","his","how","how's","i","i'd","i'll","i'm","i've","if","in","into","is","isn't","it","it's","its","itself","let's","me","more","most","mustn't","my","myself","no","nor","not","of","off","on","once","only","or","other","ought","our","ours","ourselves","out","over","own","same","shan't","she","she'd","she'll","she's","should","shouldn't","so","some","such","than","that","that's","the","their","theirs","them","themselves","then","there","there's","these","they","they'd","they'll","they're","they've","this","those","through","to","too","under","until","up","very","was","wasn't","we","we'd","we'll","we're","we've","were","weren't","what","what's","when","when's","where","where's","which","while","who","who's","whom","why","why's","with","won't","would","wouldn't","you","you'd","you'll","you're","you've","your","yours","yourself","yourselves", "this"];
    // turn document into lowercase words, remove all stopwords
    var document = document.replace(/[.,]/g, '');
    let document_in_lowercase = document.split(" ").map(function(x){ return x.toLowerCase() });
    return document_in_lowercase.filter( x => !stopwords.includes(x) );
}