Constants, Aliases

[Hasan Aljudy]

I think you're proposing a preprocessor .. something that D deliberately 
dropped from C/C++

Xinok wrote:
> In C++, you can define a constant by using a preprocessor:
> #define INT 30
> 
> In D, the standard is to use 'const':
> const int INT = 30;
> 
> The problem with the const keyword is it doesn't guarantee the expression will
> be constant.
> const int* PTR = new int; // This technically isn't a constant, the compiler
> just doesn't allow you to modify it's value.
> 
> Another solution is to use enumerators, but they don't aloow any type other
> than int:
> enum { val = 30 } // OK
> enum { str = "Hello" } // Error
> 
> 
> So I was thinking, why not give this job to aliases? Aliases must be constant,
> you can use any type with them, and they're easy to write.
> alias 30 VAL;
> alias "Hello" STR;
> alias 31.5 DEC;
> 
> Expressions can simply be put within parenthesis:
> alias (15 * 99) EXP;