The Salesforce Tower is the tallest building in San Francisco and the second tallest building west of the Mississippi River. Its grandeur was made possible by the over 18 hours’ worth of work and 49 million pounds of concrete it took to pour its foundation. Without such intense effort and substance, such a spectacular building would be vulnerable to earthquakes, sinking, and swaying that could ultimately cause the building to collapse.
Up to this point you have only been writing and evaluating expressions in the Scala REPL. Just like the foundation of the Salesforce Tower, this has been ...
