I have just checked it and yes, it works with a constant that is not an enum: `const int FOO` defined in the module namespace or `static int BAR` defined in the dummy Vm class.

On 08/14/2014 02:08 PM, Maxime Chevalier-Boisvert wrote:
> Thanks. Does it also work with a constant that's not an enum, e.g.: const int FOO?
>
> On 08/14/2014 01:23 PM, Rémy Mouëza wrote:
>> Using __traits (identifier, ...) and a template alias seems to work for me:
>>
>> import std.stdio;
>>
>> /// Two kinds of enums:
>>
>> /// A named enum.
>> enum VmParams {
>>      OBJ_MIN_CAP,
>>      PROTO_SLOT_IDX,
>>      FPTR_SLOT_IDX,
>> }
>>
>> /// An anonymous one.
>> enum {
>>      ATTR_CONFIGURABLE = 3,
>>      ATTR_WRITABLE,
>>      ATTR_ENUMERABLE,
>>      ATTR_DELETED,
>>      ATTR_GETSET,
>>      ATTR_DEFAULT
>> }
>>
>> /// A dummy Vm class for example purpose.
>> class Vm {
>>      /// Stores values.
>>      int [string] table;
>>
>>      /// The "classic" runtime const API.
>>      void defRTConst (string id, int val) {
>>          table [id] = val;
>>      }
>>
>>      /// Using an alias with the identifier trait.
>>      void rtConst (alias p) () {
>>          table [__traits (identifier, p)] = p;
>>      }
>>
>>      /// Initializes our .table member.
>>      this () {
>>          /// Using the allMembers traits we can process all the members
>> of a
>>          /// named enum.
>>          foreach (member; __traits (allMembers, VmParams)) {
>>              int value = mixin ("VmParams." ~ member);
>>              this.defRTConst (member, value);
>>          }
>>
>>          /// Without duplicating the name and its value.
>>          rtConst!ATTR_CONFIGURABLE;
>>          rtConst!ATTR_WRITABLE;
>>          rtConst!ATTR_ENUMERABLE;
>>          rtConst!ATTR_DELETED;
>>          rtConst!ATTR_GETSET;
>>          rtConst!ATTR_DEFAULT;
>>
>>          /* rtConst won't work with local variables:
>>          //  auto foo = ATTR_DEFAULT;
>>          //  rtConst!foo;
>>          The code above raises a compiler error:
>>              Error: template instance rtConst!(foo) cannot use local
>> 'foo' as parameter to non-global template rtConst(alias p)()
>>          */
>>      }
>> }
>>
>> void main ()  {
>>      Vm vm = new Vm;
>>      vm.table.writeln;
>>
>>      /// output:
>>      /// ["OBJ_MIN_CAP":0, "ATTR_WRITABLE":4, "ATTR_ENUMERABLE":5,
>> "ATTR_GETSET":7, "PROTO_SLOT_IDX":1, "FPTR_SLOT_IDX":2,
>> "ATTR_CONFIGURABLE":3, "ATTR_DELETED":6, "ATTR_DEFAULT":8]
>> }
>>
>>
>> On 08/12/2014 07:36 PM, Maxime Chevalier-Boisvert wrote:
>>> In my JavaScript VM, I have a function whose purpose is to expose D/host
>>> constants to the JavaScript runtime code running inside the VM. This
>>> makes for somewhat redundant code, as follows:
>>>
>>> vm.defRTConst("OBJ_MIN_CAP"w, OBJ_MIN_CAP);
>>> vm.defRTConst("PROTO_SLOT_IDX"w, PROTO_SLOT_IDX);
>>> vm.defRTConst("FPTR_SLOT_IDX"w, FPTR_SLOT_IDX);
>>> vm.defRTConst("ATTR_CONFIGURABLE"w  , ATTR_CONFIGURABLE);
>>> vm.defRTConst("ATTR_WRITABLE"w      , ATTR_WRITABLE);
>>> vm.defRTConst("ATTR_ENUMERABLE"w    , ATTR_ENUMERABLE);
>>> vm.defRTConst("ATTR_DELETED"w       , ATTR_DELETED);
>>> vm.defRTConst("ATTR_GETSET"w        , ATTR_GETSET);
>>> vm.defRTConst("ATTR_DEFAULT"w       , ATTR_DEFAULT);
>>>
>>> I'm just wondering if there's a way to template defRTConst so that the
>>> name of an identifier I'm passing (e.g.: ATTR_DEFAULT) can be captured
>>> by the template, making it so that I don't also need to pass the name as
>>> a string. I expect the answer to be no, but maybe someone with more
>>> knowledge of D template magic knows better.
>>

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