[blowski]

Just to play devil's advocate: sometimes DRY code is harder to understand, which makes it harder to see bugs. Whenever you introduce an abstraction to make your code DRYer, you have to remember the law of leaky abstractions. DRY code is a good principle to follow, but not an absolute law.

[atas]

Yes, and that's why you have to be extra-careful with copy-pasting :-)

[eru]

Some languages are leakier than others..

As for terse code: a line that's five times as hard to understand might be worth it, if it saves ten. (But I usually code in languages that are famously terse and have watertight abstractions---at least in the correctness sense, even if not in the performance sense.)