There’s No Such Thing as Clean Code(steveonstuff.com)

  assert(loc.x == 10.3)
  assert(loc.y == 10.4)
  assert(loc.z == 10.5)

    assertEqual(complex(1, 2) + complex(3, 5),
                complex(4, 7));

    auto c = complex(1, 2) + complex(3, 5);
    assertEqual(c.re(), 4);
    assertEqual(c.im(), 7);

    assertEqual(complex(1, 2) + complex(3, 5),
                complex(4, 7));
    assertEqual(complex(1, 2) + complex(-3, -5),
                complex(-2, -2));

  git log -p -- file

   If (thing.someBusinessDate < 2010-06-01) { doTheOldWay();} else{doTheNewWay();}

  interface TheWay{ edgecase1(); edgecase2();...}    
  class TheOldWay implements TheWay{...}
  class TheNewWay implements TheWay{...}
  class TheNewNewWay implements TheWay{...}
  TheWay wayDetector(thing){/* all the ifs here */}

    books
        .join(authors, book => book.author, author => author.id)
        .filter(([book, author]) => author.lastName === searchText)
        .map((book, author) => `The Book ${book.title}, by ${author.fullName()}, has ${book.chapters.count()} chapters, totaling ${book.chapters.sum(chapter => chapter.pages.count())} pages.`);

    /// <verboseDocs purpose="Verbosity">
    ///   <purpose> Gets the author of a book
    ///   <returns> The author of the given book
    ///   <inputs>
    ///       <input param="book">The book to get the author of
    ///   </inputs>
    /// </verboseDocs>
    function getAuthorOfBook(book: Book) {
        return book.author;
    }

    @testMethod()
    function canGetAuthorOfBook() {
        const mockBook: Book = {
          author: 'Test Author',
          title: 'Verbosity',
          ...
        };
        
        Assert.areEqual('Test Author', getAuthorOfBook(mockBook);
    }

    /// <verboseDocs>
    ///    <purpose> Takes a last name and returns a function that returns true if the given (Book, Author) tuple contains an author whose last name matches the given string of the outer function.
    /// ...
    function getBookAuthorPairPredicateFromAuthorLastName(lastName: string) {
        return function(pair: [Book, Author]) 
            return pair[1].lastName === lastName;
        }
    }

    books
        .join(authors, getAuthorOfBook, author => getIdOfAuthor)
        .filter(getBookAuthorPairPredicateFromAuthorLastName (searchText))
        .map(describeBookAuthorPair)