const?? When and why? This is ugly!

[bearophile]

hasen:
> Really? have you considered other possibilities?
> How about, adding a new attribute to functions: `pure`

D2 already implements of plans to implement both transitive immutability, pure functions and to make by default data not accessible between threads :-)
See pure here:
http://www.digitalmars.com/d/2.0/function.html
(And in the future it will probably adopt even more immutability-related idioms and data structures).

Bye,
bearophile