• Joseph (9/9) Sep 29 2017 static if ()
• arturg (9/19) Sep 29 2017 import std.traits;
• Steven Schveighoffer (6/17) Sep 29 2017 Check to see that it has a type:

Joseph <JE342 gmail.com> writes:

static if ()
{
  enum x;
}

static if (isDefined!x)
{
}

What's the correct way to check if a variable has been defined? 
(note x may or may not be defined above. I need to know if it is)

arturg <var.spool.mail700 gmail.com> writes:

On Friday, 29 September 2017 at 18:03:52 UTC, Joseph wrote:
 static if ()
 {
  enum x;
 }

 static if (isDefined!x)
 {
 }

 What's the correct way to check if a variable has been defined? 
 (note x may or may not be defined above. I need to know if it 
 is)

import std.traits;
static if(hasMember!(T, "x"))
{
}

or if at module level

static if(__traits(hasMember, mixin(__MODULE__), "x"))
{
}

Steven Schveighoffer <schveiguy yahoo.com> writes:

On 9/29/17 2:03 PM, Joseph wrote:
 static if ()
 {
   enum x;
 }
 
 static if (isDefined!x)
 {
 }
 
 What's the correct way to check if a variable has been defined? (note x 
 may or may not be defined above. I need to know if it is)

Check to see that it has a type:

static if(is(typeof(x)))
{
}

-Steve