Re: Memoization in compile-time

[Dennis Ritchie via Digitalmars-d-learn]

On Friday, 13 March 2015 at 18:38:16 UTC, Ali Çehreli wrote:
On 03/13/2015 11:28 AM, Ali Çehreli wrote:
> enum int[] factorials = memoizeFactorials(N);

Oops! That's generally a trap! The array better be 'static' 
because a manifest constant like 'enum factorials' would be 
inserted everywhere it is used. (Similar to a C macro.)

I've been scratching my head why the assertion below was 
failing.

It sould be 'static':

static int[] factorials = memoizeFactorials(N);

If it's an enum, the following assert will fail:

    foreach (i; 0 .. N) {
        assert(factorials.ptr + i == &(factorials[i]));
    }

Make it a 'static', it will pass because then there will be 
just one factorials array.

Ali

Thanks.

And you can make the same memoized variable was available at 
compile time and at run time? :)