On Tuesday, 17 March 2015 at 11:48:15 UTC, Nick Treleaven wrote:
On 17/03/2015 10:31, Almighty Bob wrote:
It's far more useful for csvReader to return a type I know and
can use than it is to obscure the return type for the sake of
some philosophical ideal of increasing encapsulation.
Part of the art of API design is to hide implementation where
it's not necessarily needed. Designers might err on the side of
hiding things, because how you expose something is important as
it has to be maintained indefinitely. If they expose everything
then the internals can never be redesigned for better
performance, etc.
They don't increase encapsulation. The public members of a
voldomort type are still public, you still have to code to the
API of the return type whether it's a regular or voldomort type.
You can keep as much private or public in either case as you like.
All they do take the typename out of circulation, they make life
harder for the user. There's no benefit. None.
But at least the library author can stroke his chin a feel smug
that there's one less type in the modules' namespace.
