On 10/21/2015 07:25 PM, Andrei Alexandrescu wrote:
It seems to me that's a departure from traditional persistent data structures.
I don't think so.
Those have immutable elements;
Immutable insofar as the elements themselves don't change. It is easy to create a persistent list of immutable references to mutable data in Haskell, for instance.
far as I can tell you discuss containers that only have immutable topology. -- Andrei
The topology as well as all the elements are immutable, just not in the 'transitive qualifier' way. Immutable references to mutable data are useful, they just don't have built-in language support. Persistent data structures work perfectly fine with those.
