Template/mixin ideas?

[Chris Katko]

On Wednesday, 3 October 2018 at 11:51:01 UTC, Sebastiaan Koppe 
wrote:
> On Wednesday, 3 October 2018 at 11:01:53 UTC, Chris Katko wrote:
>> [...]
>
> A combination of static introspection with string mixins does 
> the trick:
>
> ---
> enum colors {
>     reset = "\033[0m",
>     red = "\033[31m"
> }
>
> auto GenerateColorFuncs() {
>     string result;
>     static foreach(c; __traits(allMembers, colors))
>         result ~= "auto "~c~"(string str) { return colors."~c~" 
> ~ str ~ colors.reset; }";
>     return result;
> }
>
> mixin(GenerateColorFuncs());
>
> void main()
> {
>     import std.stdio;
>     writeln("bla".red);
> }
> ---
>
> Although you might want to replace the string concatenation 
> with something more performant if used a lot.

The mixin part wouldn't be slowed by strings, right? So the 
"slowness" is the invokation part which changes strings and 
forces GC allocations, I guess?

What's the alternative to using strings... for strings?