I thought D was proud of compilation times and claimed to be useful as a scripting language?
However, D's compile-time metaprogramming facilities allowed us to get ambitious in some places... for instance, std.uni precomputes some Unicode lookup tables during compilation, and std.regex makes heavy use of metaprogramming to compile regular expression strings to D code, again during compilation. As a result, making use of those features will result in heavier load on the compiler.
On the other hand, for the little things it would be weird. Would you do that for a single regular expression?