submitting for pre-eval

main.js

@@ -1 +1,113 @@
 // write your code here to make the tests pass
+//
+/* A Library module which should have 3 public functions:
+ -- addBook which simply adds new books to the library's private books array. 
+ -- checkOutBook which takes a book object as an argument and changes its checkedOut attribute to true, 
+  but ONLY if that book exists in the library. Otherwise, just console log some kind of error. 
+  -- returnBook which takes a book object as an argument and changes its checkedOut attribute to false, 
+    but ONLY if that book exists in the library. Otherwise, just console log some kind of error.
+
+A Book module which should have 2 public functions:
+ -- getAttribute, which should take one argument, the name of one of the book's attributes, 
+  and return it, but only if that attribute is a key on the Book module's attributes object. 
+  -- setAttribute, which should take two arguments, the name of one of the book's attributes 
+    and set it on the book's attributes object, but only if that attribute is a key 
+    on the Book module's attributes object. 
+*/
+
+var Library = function() {
+  var books = [];  // make an array of objects for books in library
+
+  var addBook = function(book) {
+    console.log('addBook() called');
+    console.log(typeof(book));
+    console.log(book);
+    console.log(book.getAttribute('title'));
+    console.log(book.getAttribute('checkedOut'));
+    books.push(book);
+    console.log('addBook books after ');
+    console.log(books);
+  };
+
+  var checkOutBook = function(book) {  
+    console.log('checkOutBook() called');
+    console.log('books.includes(book) value ' + books.includes(book));
+    if (books.includes(book)) {
+      // and if Book attributes checkedOut === true
+      console.log('found ' + book);
+      let indexOfBook = books.indexOf(book);
+
+      console.log(books[indexOfBook].getAttribute('checkedOut'));
+      if (books[indexOfBook].getAttribute('checkedOut') === false) {
+        console.log('-->made it to the changing of checkedOut');
+        books[indexOfBook].setAttribute('checkedOut', true);
+      } else {
+        console.log(book + ' is already checked out.');
+      }
+      console.log(book + ' is not in the library.'); 
+    }
+  }
+
+  var returnBook = function(book) { 
+    console.log('returnBook() called');
+    if (!books.includes(book)) {
+       console.log('book does not belong to this library');
+       return;
+      }
+    console.log(book + ' belongs to library.');
+    if (book.getAttribute('checkedOut') === false) {
+      console.log('...but we already have this book.');
+      } else {
+      book.setAttribute('checkedOut', false);
+      console.log(book + 'has been returned. Thank you.');
+    }
+  };
+
+
+
+  var listBooks = function() {  // this is not in specs, but hoped to use for testing. It doesn't work.
+    for (var i = 0; i < books.length; i += 1) {
+      console.log('title: ' + books[i](getAttribute('title')));
+      console.log('checked out? ' + books[i](getAttribute('checkedOut')));
+    }
+  };
+
+  return {
+    addBook: addBook,
+    checkOutBook: checkOutBook,
+    returnBook: returnBook,
+    listBooks: listBooks  // not in spec, fails anyway. Why?
+  };
+};
+
+var Book = function(title) {
+  var attributes = {
+    title: title,
+    checkedOut: false
+  };
+
+  var getAttribute = function(lookFor) {
+    console.log('getAttribute() called');
+    console.log('that attribute is' + lookFor);
+    console.log('and its value is ' + attributes[lookFor]);
+    if (lookFor in attributes) {  
+      console.log('it associated ' + attributes[lookFor]);
+      return attributes[lookFor];
+    }
+  };
+
+  var setAttribute = function(attr, setting) {
+    console.log('setAttribute() called');
+    if (attr in attributes) {
+      attributes[attr] = setting;
+      console.log('result of setAttribute: ' +     attributes[attr]);
+    } else {   // I think this can be skipped... 
+      return;}  // ...along with this
+  };
+
+  return {
+    getAttribute: getAttribute,
+    setAttribute: setAttribute
+  };
+};
+