On Monday, 28 April 2014 at 13:57:56 UTC, Andrej Mitrovic wrote:
On Monday, 28 April 2014 at 13:52:52 UTC, ParticlePeter wrote:
DMD tells me "Error: variable m cannot be read at compile
time", but why ?
Because 'static foreach' is not an explicit feature yet, so it
depends on the context. When you wrap the trait via:
[__traits(allMembers, MyStruct)]
You're creating an array, and foreach will *not* by default
attempt to become a static foreach, even if the array is known
at compile-time. If you remove the parentheses it will work.
You've had a few bugs in the mixin code though, anyway here's
the working sample:
-----
import std.stdio;
struct MyStruct
{
float float_value = 0.0f;
ubyte ubyte_value = 2;
}
enum members = __traits(allMembers, MyStruct);
void main()
{
foreach (m; members)
{
mixin("writeln( `" ~ m ~ "` , \" : \" , ( MyStruct." ~
m ~ ".offsetof ) );");
}
}
-----
Thank you very much, it works. I never came so far to see those
mixin errors at all :-)
I found the code with parenthesis in the dlang __traits docs and
also Philippe Sigauds "D Templates", and I haven't seen any other
example which works without them. So, when to use which syntax (
for which purpose ) ? Is this clarified somewhere ?
Regards, ParticlePeter
