DRY is not a surface metric, although it is often misunderstood as one. The original formulation of DRY was: "Every piece of knowledge must have a single, una

DRY is not a surface metric, although it is often misunderstood as one. The original formulation of DRY was: "Every piece of knowledge must have a single, unambiguous, authoritative representation within a system." Elimination of syntactic repetition is not an application of DRY, although application of DRY will often incidentally eliminate syntactic repetition.