I need to check on struct members is match a delegate type.  for example;

alias Type = scope void delegate(int) @nogc  ;
struct S {
     void onMatch1(int) scope @nogc {
    }

     void onNotMatch2(int) scope  {
    }

    void onNotMatch2(int, int) scope @nogc {
    }

     Type not_match3;
}

please notify not_match3 member is should return false, I try this template but not work:



template isDelegateMember(S, string name, D) if(is(S == struct) && __traits(hasMember, S, name) && is( D == delegate ) ) {
    alias Fn    = typeof( __traits(getMember, S.init, name) );
    static assert( isFunction!Fn );
    pragma(msg, D);
    pragma(msg, typeof(D.init.funcptr));
    pragma(msg, Fn );
    pragma(msg, __traits(isSame, Fn, typeof(D.init.funcptr)) );
    enum isDelegateMember = is( Fn == typeof(D.init.funcptr) ) ;
}

On Tuesday, 30 July 2019 at 10:06:21 UTC, Newbie2019 wrote:
>
> template isDelegateMember(S, string name, D) if(is(S == struct) && __traits(hasMember, S, name) && is( D == delegate ) ) {
>     alias Fn    = typeof( __traits(getMember, S.init, name) );
>     static assert( isFunction!Fn );
>     pragma(msg, D);
>     pragma(msg, typeof(D.init.funcptr));
>     pragma(msg, Fn );
>     pragma(msg, __traits(isSame, Fn, typeof(D.init.funcptr)) );
>     enum isDelegateMember = is( Fn == typeof(D.init.funcptr) ) ;
> }


foreach(int name_index, name; __traits(allMembers, S) ) static if( isDelegateMember!(S, name, Type) ) {
    enum Rules = getUDAs!( __traits(getMember, S, name) , Rule);
     // handle the member is match this rules.
}

On Tuesday, 30 July 2019 at 10:08:55 UTC, Newbie2019 wrote:
> foreach(int name_index, name; __traits(allMembers, S) ) static if( isDelegateMember!(S, name, Type) ) {
>     enum Rules = getUDAs!( __traits(getMember, S, name) , Rule);
>      // handle the member is match this rules.
> }


And one more question, how to get the Function address or delegate address of a struct member
 on compile time ?

struct S {
    void onMatch(){}
}


__gshared auto onMatch = (&(S.init)).funcptr ;  // this not work