Compilation constants

[bearophile]

In a C program I have a numeric constant SIZE (that is in [1,32]), that I can define when I compile the code, like this:
gcc -DSIZE=14 ...

How can I do the same thing in D? The solution I have found is to put in the D code:
version(B1) const SIZE = 1;
version(B2) const SIZE = 2;
version(B3) const SIZE = 3;
version(B4) const SIZE = 4;
...
version(B14) const SIZE = 14;
...

And then compile the D program with:
dmd -version=B14 ...
Or:
ldc -d-version=B14 ...

Do you know nicer ways to do this in D? (if there are no nicer ways, is this simple feature worth adding to D?)

Thank you, bye,
bearophile