When clients ask me to help them with legacy code it generally takes less than 30 minutes for me to run into a debilitating constructor—a term I use to describe a constructor that does too much. You might think me melodramatic for calling it “debilitating”, but these constructors not only slow us down when we try to understand the code, but block our every effort to improve it. These constructors often hardwire a dependency either to some horrifying external resource (a database or a we...
