Joe Duffy's "Thoughts on immutability and concurrency"

[bearophile]

Jesse Phillips:
> I must not be understanding something in his use of immutability. For his spellchecker example he suggested making a copy of some portion of the document into an immutable data-structure so that it can be shared without locks or copying. How is this better than message passing of mutable data?

To know the answer you need to know what a piece-table is, here you can find some info:
http://www.cs.unm.edu/~crowley/papers/sds/node15.html
You can find the missing images here:
http://www.cs.unm.edu/~crowley/papers/sds.pdf

Bye,
bearophile