Reply to Bill,
On Sun, Nov 30, 2008 at 6:05 AM, dfgh <[EMAIL PROTECTED]> wrote:
Warning: this would break existing code.
I have an idea for a completely new template syntax that is easier to
use and implement. I'll explain it in therms of a hypothetical
language called Dscript. Let's start by imagining that Dscript works
identically to D 2.0, but it is interpreted and dynamically typed,
with eval's (this is not intended to be implemented, and not the main
point of this post). Obviously there isn't much of a point to
creating two languages with the same syntax, especially since Dscript
would be useless for systems programming, contradicting one of the
design goals of D. However, there are some things that you can't do
if you have static type enforcement. For example, in D this is
impossible:
template foo(string Type) {
invariant foo = eval(Type ~ ".init");
}
Actually something similar is possible in current D with string
mixins. But they have to be full statements and not expressions.
template foo(string Type) {
mixin("invariant foo = "~Type~".init;");
}
this works:
int i = mixin("5");
import std.stdio;
void main(){writef("%d\n", i);}
http://codepad.org/1a14zKsl
But it might be nice if string mixins worked for expressions too. I
presume there's some reason Walter didn't make them work as
expressions, though.
