Ramifications of const

[Georg Wrede]

Jari-Matti Mäkelä wrote:
> I don't believe D is going to be purely functional anywhere in the near
> future. There was only talk about constness of e.g. function parameters and
> certain variables.

The day D gets purely functional, I'm outta here!

But, several aspects that relate to recognizing functions as purely 
functional or not, do give us both immediate benefits as well as open up 
avenues for significant gains in the future.

A language that handles (and understands) smoothly both functional and 
non-functional code, is in a position to reap the benefits from both 
worlds. This is no more peculiar than the fact that D is an excellent 
language for both OO and non-OO programming, as well as mixed OO/non-OO 
programming.

We are already using pure functions (like sin(x), abs(x), etc.) in our 
code, and this does not have to become any more complicated than that. 
But for the compiler, optimizer, parallel code generator, and some other 
future things, knowing which functions are Pure, is simply essential.