• Jeremie Pelletier (3/3) Jul 29 2009 Could it be a valid option to have a shorthand template syntax if the te...
• Daniel Keep (13/17) Jul 29 2009 Aside from that not being how alias works,
• Lars T. Kyllingstad (10/11) Jul 30 2009 ?: already works at compile time, at least in D2. I use it all the time.

Jeremie Pelletier <jeremiep gmail.com> writes:

Could it be a valid option to have a shorthand template syntax if the template
body has only one statement? Something like:

template Tuple(A...) alias Tuple = A;

Another suggestion would be to have the ?: syntax supported for static
statements, as we're currently forced to use static ifs. It really adds a lot
of code to templates for even simple conditions.

Daniel Keep <daniel.keep.lists gmail.com> writes:

Jeremie Pelletier wrote:
 Could it be a valid option to have a shorthand template syntax if the template
body has only one statement? Something like:
 
 template Tuple(A...) alias Tuple = A;

Aside from that not being how alias works,

template Tuple(A...) alias A Tuple;

template Tuple(A...) { alias A Tuple; }

You're saving two characters; hardly seems worth it, to me.  That said,
I can't think of any technical reason why you couldn't change the
grammar to allow for a single declaration.

 Another suggestion would be to have the ?: syntax supported for static
statements, as we're currently forced to use static ifs. It really adds a lot
of code to templates for even simple conditions.

I don't think using ?: for statements is a good idea; it's only ever
suitable for very small expressions.

The problem there is that there would be no way to distinguish between a
compile-time ?: and a run-time ?: for either the compiler or the
programmer.  I have enough grief with CTFE and kinda-static foreach, I
don't want to see another construct like that added.

"Lars T. Kyllingstad" <public kyllingen.NOSPAMnet> writes:

Jeremie Pelletier wrote:
 Another suggestion would be to have the ?: syntax supported for static
statements, as we're currently forced to use static ifs. It really adds a lot
of code to templates for even simple conditions.


?: already works at compile time, at least in D2. I use it all the time.

   template cat(string a, string b, bool addSpace)
   {
       enum string cat = a ~ (addSpace ? " " : "") ~ b;
   }

   static assert (cat!("foo", "bar", false) == "foobar");
   static assert (cat!("foo", "bar", true) == "foo bar");

Is that what you meant?

-Lars