On 10/21/2015 01:42 PM, Ulrich Kuettler wrote:
On Wednesday, 21 October 2015 at 11:05:12 UTC, Andrei Alexandrescu wrote:
I'm finally getting the cycles to get to thinking about Design by
Introspection containers. First off, there are several general
categories of containers. I think D should support all properly. One
question is which we go for in the standard library.
1. Functional containers.
Very much in favor of functional (or persistent) containers. Immutable.
Value semantics.
This might take some getting used to, but if properly designed these
containers would be killer for D. A dream come true.
I agree they're cool.
These are immutable; once created, neither their topology nor their
elements may be observably changed. Manipulating a container entails
creating an entire new container, often based on an existing container
(e.g. append takes a container and an element and creates a whole new
container).
Internally, functional containers take advantage of common
substructure and immutability to share actual data. The classic
resource for defining and implementing functional containers is
http://www.amazon.com/Purely-Functional-Structures-Chris-Okasaki/dp/0521663504.
An insanely beautiful example is clojure's PersistantVector. AFAIK it
made its way into Scala, too.
Far as I understand from
http://hypirion.com/musings/understanding-persistent-vector-pt-1, it's
that tree thing with carefully chosen slot sizes for cache friendliness?
Andrei
