digitalmars.D.learn - enum and static if

Namespace (11/11) Mar 11 2015 This code does not work:

ketmar (3/16) Mar 11 2015 nope. `static if` is statement, so it works only where statement is=20

wobbles (7/24) Mar 11 2015 You can do something like

ketmar (3/29) Mar 11 2015 sure, but you have to copypaste the whole enum in both places. maybe=20

Artur Skawina via Digitalmars-d-learn (9/40) Mar 11 2015 mixin(`

ketmar (4/45) Mar 11 2015 yes, it works. it also can be a participant in "ugly D code of the month...

Nicolas Sicard (10/59) Mar 11 2015 The second prize in this contest could for:

Namespace (2/19) Mar 11 2015 Thanks, I've hoped that 'static if' is a full replacement for #if

Jonathan M Davis via Digitalmars-d-learn (11/12) Mar 11 2015 Walter Bright has a rather dim view of #if and friends in C/C++ given ho...

"Namespace" <rswhite4 gmail.com> writes:

This code does not work:

----
enum Test {
     Foo,
static if (__VERSION__ >= 2067)
     Bar,
}
     Quatz
}
----

Any chance that this could work?

Mar 11 2015

ketmar <ketmar ketmar.no-ip.org> writes:

On Wed, 11 Mar 2015 13:48:45 +0000, Namespace wrote:

 This code does not work:
=20
 ----
 enum Test {
      Foo,
 static if (__VERSION__ >=3D 2067)
      Bar,
 }
      Quatz
 }
 ----
=20
 Any chance that this could work?

nope. `static if` is statement, so it works only where statement is=20
allowed. the same is true for `version`. this is by design.=

Mar 11 2015

"wobbles" <grogan.colin gmail.com> writes:

On Wednesday, 11 March 2015 at 14:34:32 UTC, ketmar wrote:
 On Wed, 11 Mar 2015 13:48:45 +0000, Namespace wrote:

 This code does not work:
 
 ----
 enum Test {
      Foo,
 static if (__VERSION__ >= 2067)
      Bar,
 }
      Quatz
 }
 ----
 
 Any chance that this could work?

 nope. `static if` is statement, so it works only where 
 statement is
 allowed. the same is true for `version`. this is by design.

You can do something like
static if (__VERSION__ >= 2067)
     enum Test{ ... }
else
     enum Test{ ... }

as a workaround?

Mar 11 2015

ketmar <ketmar ketmar.no-ip.org> writes:

On Wed, 11 Mar 2015 14:36:07 +0000, wobbles wrote:

 On Wednesday, 11 March 2015 at 14:34:32 UTC, ketmar wrote:
 On Wed, 11 Mar 2015 13:48:45 +0000, Namespace wrote:

 This code does not work:
=20
 ----
 enum Test {
      Foo,
 static if (__VERSION__ >=3D 2067)
      Bar,
 }
      Quatz
 }
 ----
=20
 Any chance that this could work?

 nope. `static if` is statement, so it works only where statement is
 allowed. the same is true for `version`. this is by design.

=20
 You can do something like static if (__VERSION__ >=3D 2067)
      enum Test{ ... }
 else
      enum Test{ ... }
=20
 as a workaround?

sure, but you have to copypaste the whole enum in both places. maybe=20
allowing `version` in enums worth a ER...=

Mar 11 2015

Artur Skawina via Digitalmars-d-learn <digitalmars-d-learn puremagic.com> writes:

On 03/11/15 15:41, ketmar via Digitalmars-d-learn wrote:
 On Wed, 11 Mar 2015 14:36:07 +0000, wobbles wrote:
 
 On Wednesday, 11 March 2015 at 14:34:32 UTC, ketmar wrote:
 On Wed, 11 Mar 2015 13:48:45 +0000, Namespace wrote:

 This code does not work:

 ----
 enum Test {
      Foo,
 static if (__VERSION__ >= 2067)
      Bar,
 }
      Quatz
 }
 ----

 Any chance that this could work?

 nope. `static if` is statement, so it works only where statement is
 allowed. the same is true for `version`. this is by design.

 You can do something like static if (__VERSION__ >= 2067)
      enum Test{ ... }
 else
      enum Test{ ... }

 as a workaround?

 
 sure, but you have to copypaste the whole enum in both places. maybe 
 allowing `version` in enums worth a ER...

   mixin(`
   enum Test {
       Foo,`
   ~(__VERSION__>=2067?`
       Bar,`:``)
   ~`  Quatz
   }`);

artur

Mar 11 2015

ketmar <ketmar ketmar.no-ip.org> writes:

On Wed, 11 Mar 2015 18:17:38 +0100, Artur Skawina via Digitalmars-d-learn
wrote:

 On 03/11/15 15:41, ketmar via Digitalmars-d-learn wrote:
 On Wed, 11 Mar 2015 14:36:07 +0000, wobbles wrote:
=20
 On Wednesday, 11 March 2015 at 14:34:32 UTC, ketmar wrote:
 On Wed, 11 Mar 2015 13:48:45 +0000, Namespace wrote:

 This code does not work:

 ----
 enum Test {
      Foo,
 static if (__VERSION__ >=3D 2067)
      Bar,
 }
      Quatz
 }
 ----

 Any chance that this could work?

 nope. `static if` is statement, so it works only where statement is
 allowed. the same is true for `version`. this is by design.

 You can do something like static if (__VERSION__ >=3D 2067)
      enum Test{ ... }
 else
      enum Test{ ... }

 as a workaround?

=20
 sure, but you have to copypaste the whole enum in both places. maybe
 allowing `version` in enums worth a ER...

=20
    mixin(`
    enum Test {
        Foo,`
    ~(__VERSION__>=3D2067?`
        Bar,`:``)
    ~`  Quatz }`);
=20
 artur

yes, it works. it also can be a participant in "ugly D code of the month"=20
contest. ;-)=

Mar 11 2015

"Nicolas Sicard" <dransic gmail.com> writes:

On Wednesday, 11 March 2015 at 17:19:20 UTC, ketmar wrote:
 On Wed, 11 Mar 2015 18:17:38 +0100, Artur Skawina via 
 Digitalmars-d-learn
 wrote:

 On 03/11/15 15:41, ketmar via Digitalmars-d-learn wrote:
 On Wed, 11 Mar 2015 14:36:07 +0000, wobbles wrote:
 
 On Wednesday, 11 March 2015 at 14:34:32 UTC, ketmar wrote:
 On Wed, 11 Mar 2015 13:48:45 +0000, Namespace wrote:

 This code does not work:

 ----
 enum Test {
      Foo,
 static if (__VERSION__ >= 2067)
      Bar,
 }
      Quatz
 }
 ----

 Any chance that this could work?

 nope. `static if` is statement, so it works only where 
 statement is
 allowed. the same is true for `version`. this is by design.

 You can do something like static if (__VERSION__ >= 2067)
      enum Test{ ... }
 else
      enum Test{ ... }

 as a workaround?

 
 sure, but you have to copypaste the whole enum in both 
 places. maybe
 allowing `version` in enums worth a ER...

 
    mixin(`
    enum Test {
        Foo,`
    ~(__VERSION__>=2067?`
        Bar,`:``)
    ~`  Quatz }`);
 
 artur

 yes, it works. it also can be a participant in "ugly D code of 
 the month"
 contest. ;-)

The second prize in this contest could for:

mixin(`
     enum Test {
         Foo,
         %s
         Quatz
     }`
.format(__VERSION__ >= 2067 ? "Bar," : ""));

:)

Mar 11 2015

"Namespace" <rswhite4 gmail.com> writes:

On Wednesday, 11 March 2015 at 14:34:32 UTC, ketmar wrote:
 On Wed, 11 Mar 2015 13:48:45 +0000, Namespace wrote:

 This code does not work:
 
 ----
 enum Test {
      Foo,
 static if (__VERSION__ >= 2067)
      Bar,
 }
      Quatz
 }
 ----
 
 Any chance that this could work?

 nope. `static if` is statement, so it works only where 
 statement is
 allowed. the same is true for `version`. this is by design.

Thanks, I've hoped that 'static if' is a full replacement for #if

Mar 11 2015

Jonathan M Davis via Digitalmars-d-learn writes:

On Wednesday, March 11, 2015 14:55:01 Namespace via Digitalmars-d-learn wrote:
 Thanks, I've hoped that 'static if' is a full replacement for #if

Walter Bright has a rather dim view of #if and friends in C/C++ given how
often he's seen them abused, which is why version and static if are more
restricted in D - in particular, it's why version won't take a boolean
expression. And while some folks get really annoyed about having to
duplicate code for different versions, he seems to be of the opinion that
that's the right way to do it and that the C/C++ way is incredibly
error-prone. Personally, I'd say that this particular use case probably
would be fine, but it would complicate how static if works, so I suspect
that he'd be against it.

- Jonathan M Davis

Mar 11 2015

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digitalmars.D.learn - enum and static if