• mimi (14/14) May 26 2013 Hi!
• evilrat (4/18) May 26 2013 std.traits and built-in traits should do what u asking.
• jerro (36/50) May 26 2013 To get a TypeTuple containing this information you can do this:
• mimi (1/1) May 26 2013 Wow! thanks!
• Diggory (5/6) May 26 2013 "offsetof" will automatically distribute over the arguments so to

"mimi" <4.deniz.z.z gmail.com> writes:

Hi!

I am want to get list of fields types and offsets in struct by
the template.

I.e., lookup through this struct:

struct S {

int a;
string b;
someptr* c;

};

template Lookup!( S )(); returns something as:





How I can do this?

"evilrat" <evilrat666 gmail.com> writes:

On Sunday, 26 May 2013 at 14:19:13 UTC, mimi wrote:
 Hi!

 I am want to get list of fields types and offsets in struct by
 the template.

 I.e., lookup through this struct:

 struct S {

 int a;
 string b;
 someptr* c;

 };

 template Lookup!( S )(); returns something as:





 How I can do this?

std.traits and built-in traits should do what u asking.

http://dlang.org/phobos/std_traits.html
http://dlang.org/traits.html

"jerro" <a a.com> writes:

On Sunday, 26 May 2013 at 14:19:13 UTC, mimi wrote:
 Hi!

 I am want to get list of fields types and offsets in struct by
 the template.

 I.e., lookup through this struct:

 struct S {

 int a;
 string b;
 someptr* c;

 };

 template Lookup!( S )(); returns something as:





 How I can do this?

To get a TypeTuple containing this information you can do this:

template Lookup(S)
{
     template Field(int index_, Type_, int offset_)
     {
         enum index = index_;
         alias Type = Type_;
         enum offset = offset_;
     }

     template impl(int i)
     {
         static if(i == S.tupleof.length)
             alias impl =  TypeTuple!();
         else
             alias impl = TypeTuple!(
                 Field!(i, typeof(S.tupleof[i]), 
S.init.tupleof[i].offsetof),
                 impl!(i + 1));
     }

     alias Lookup = impl!0;
}

If you only want to format this information to a string it's even 
simpler:

string lookup(S)()
{
     auto r = "";
     S s;
     foreach(i, e; s.tupleof)

             i, typeof(s.tupleof[i]).stringof, 
s.tupleof[i].offsetof);

     return r;
}


Then lookup!S will give you the string and you can use it at 
compile time or at run time.

"mimi" <4.deniz.z.z gmail.com> writes:

Wow! thanks!

"Diggory" <diggsey googlemail.com> writes:

On Sunday, 26 May 2013 at 23:37:01 UTC, mimi wrote:
 Wow! thanks!

"offsetof" will automatically distribute over the arguments so to 
get the offsets of a tuple you can just do:

auto tmp = TP.offsetof;

And "tmp" will be a tuple of the offsets.