paulos-palindrome/index.js

__An NPM module sample.__ _Usage:_ ```javascript npm install paulos-palindrome let Phrase = require('paulos-palindrome') let string = new Phrase("Did I do, O God, did I as I said I’d do? Good! I did.") console.log(string.palindrome()) ```

module.exports = Phrase

// Adds 'reverse' to all strings
String.prototype.reverse = function(){
  return Array.from(this).reverse().join('')
}

// Defines a Phrase object
function Phrase(content){
  this.content = content;

  // Returns content processed for palindrome testing
  this.processedContent = function processedContent(){
    return this.letters().toLowerCase()
  }

  // Returns the letters in the content. For example:
  //   new Phrase("Hello, world!").letters() === 'Helloworld'
  this.letters = function letters() {
    const lettersRegEx = /[a-z]/gi;
    return (this.content.match(lettersRegEx) || []).join('')
  }

  // Returns true if the phrase is a palindrome, false otherwise
  this.palindrome = function palindrome(){
    if (this.processedContent()){
      return this.processedContent() == this.processedContent().reverse()
    } else {
      return false
    }
  }
}