On Thu, 09 May 2013 09:38:29 -0400, Dicebot <m.stras...@gmail.com> wrote:
On Thursday, 9 May 2013 at 13:27:35 UTC, Steven Schveighoffer wrote:template GetString(T) if (is(T == int) || is(T == float) || ...) { enum string GetString = T.stringof; }Current idiomatic D way to handle both built-in types and symbols looks like this:template Hello(T...) if (T.length == 1) { static if (is(T[0])) // ... else // ... }I actually don't understand why it accepts literals as those are not symbols and, for example, you can't attach UDA to literal.
I think it was a happy accident, or else a relaxation of the rules to allow more flexibility. Possibly the same reason could be used to relax the rules again. But I think it would be a more difficult prospect in the compiler.
alias cannot accept literals in a normal alias statement. But what allowing it for template alias parameters does is enable the whole std.algorithm acceptance of a string literal for function lambdas. Arguably, this is no longer needed due to the new lambda syntax (but I think we have found other uses for it). It has also caused some headaches:
map!"a.x"(foo) is a different instantiation with identical code to: map!" a.x"(foo) -Steve
