Chris Dew:
Does D have "structural sharing" of its immutable collections?
i.e. Can I make a copy of an immutable Map or List collection
with an extra (or mutated) member, and will the returned (new)
collection share most of it's structure with the earlier
collection.
Currently Phobos doesn't have a Map (there are built-in
associative arrays), and there isn't a true List (there is a
linked list, that so far I have not used).
Currently I think nothing in D works as you ask, it doesn't even
have "immutable collections" like a Finger Tree or something.
But writing such collections is well within D type system
capabilities, so I think eventually they will be present in
Phobos if there is enough need.
Bye,
bearophile
