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digitalmars.D.learn - enum detection

reply "Jack Applegame" <japplegame gmail.com> writes:
How to detect enum member?

struct A {
   enum id = 10;
   int b;
   char c;
}
foreach(ident; __traits(allMembers, A)) {
   // is ident enum or not?
}
Nov 22 2012
next sibling parent Andrej Mitrovic <andrej.mitrovich gmail.com> writes:
On 11/22/12, Jack Applegame <japplegame gmail.com> wrote:

 How to detect enum member?

 struct A {
    enum id = 10;
    int b;
    char c;
 }
 foreach(ident; __traits(allMembers, A)) {
    // is ident enum or not?
 }



That's not an enum, that's a manifest constant. This is an enum:
struct A {
enum id { x = 10 }
}

You can use:

struct A
{
    enum id = 10;
    int b;
    char c;
}

template isEnum(alias symb)
{
    static if (is(symb == enum))
        enum bool isEnum = true;
    else
        enum bool isEnum = false;
}

void main()
{
    foreach(ident; __traits(allMembers, A))
    {
        static if (isEnum!(__traits(getMember, A, ident)))
        {
            pragma(msg, ident, " yes");
        }
    }
}
Nov 22 2012
prev sibling next sibling parent "bearophile" <bearophileHUGS lycos.com> writes:
Jack Applegame:


 How to detect enum member?

 struct A {
   enum id = 10;
   int b;
   char c;
 }
 foreach(ident; __traits(allMembers, A)) {
   // is ident enum or not?
 }



Have you tried is(ident == enum) ?

Bye,
bearophile
Nov 22 2012
prev sibling next sibling parent "Kenji Hara" <k.hara.pg gmail.com> writes:
On Thursday, 22 November 2012 at 15:10:08 UTC, Jack Applegame 
wrote:

 How to detect enum member?

 struct A {
   enum id = 10;
   int b;
   char c;
 }
 foreach(ident; __traits(allMembers, A)) {
   // is ident enum or not?
 }



Actual field might have `offsetof` builtin property.

(not tested)
   static if (is(typeof(mixin("A."~ident~".offsetof")))) {}

Kenji Hara
Nov 22 2012
prev sibling next sibling parent "bearophile" <bearophileHUGS lycos.com> writes:
 Have you tried is(ident == enum) ?



Sorry, ignore this answer, I was too much distracted.

Bye,
bearophile
Nov 22 2012
prev sibling next sibling parent "Jack Applegame" <japplegame gmail.com> writes:
On Thursday, 22 November 2012 at 17:36:03 UTC, Kenji Hara wrote:

 Actual field might have `offsetof` builtin property.

 (not tested)
   static if (is(typeof(mixin("A."~ident~".offsetof")))) {}



Yes, it works! Thanks.
Nov 22 2012
prev sibling parent "Jack Applegame" <japplegame gmail.com> writes:
On Thursday, 22 November 2012 at 17:36:03 UTC, Kenji Hara wrote:

 Actual field might have `offsetof` builtin property.

 (not tested)
   static if (is(typeof(mixin("A."~ident~".offsetof")))) {}



Yes, it works! Thanks.
Nov 22 2012