• teo <teo.ubuntu yahoo.com> Mar 21 2011
• "Simen kjaeraas" <simen.kjaras gmail.com> Mar 21 2011
• Jonathan M Davis <jmdavisProg gmx.com> Mar 21 2011
• teo <teo.ubuntu yahoo.com> Mar 21 2011

teo <teo.ubuntu yahoo.com> writes:

I cannot initialize immutable class members inside a static this() 
constructor. Is there any reason for that?

Example:
class Test
{
    public immutable(int) x;
    static this()
    {
        x = 1; // Error: variable Test.x can only initialize const x 
inside constructor
    }
}

"Simen kjaeraas" <simen.kjaras gmail.com> writes:

On Mon, 21 Mar 2011 22:27:17 +0100, teo <teo.ubuntu yahoo.com> wrote:

 I cannot initialize immutable class members inside a static this()
 constructor. Is there any reason for that?

 Example:
 class Test
 {
     public immutable(int) x;
     static this()
     {
         x = 1; // Error: variable Test.x can only initialize const x
 inside constructor
     }
 }


Non-static class members require a this pointer, and thus cannot be
initialized in a static constructor. However, if that is the error
message you get, it is clearly misleading.

-- 
Simen

Jonathan M Davis <jmdavisProg gmx.com> writes:

 On Mon, 21 Mar 2011 22:27:17 +0100, teo <teo.ubuntu yahoo.com> wrote:
 I cannot initialize immutable class members inside a static this()
 constructor. Is there any reason for that?
 
 Example:
 class Test
 {
 
     public immutable(int) x;
     static this()
     {
     
         x = 1; // Error: variable Test.x can only initialize const x
 
 inside constructor
 
     }
 
 }


 Non-static class members require a this pointer, and thus cannot be
 initialized in a static constructor. However, if that is the error
 message you get, it is clearly misleading.


No. Error message is essentially correct, just confusing. In this case, x is a 
member variable, _not_ a class/static variable. So, it must either be directly 
initialized

public immutable int x = 1;

or in a constructor (and in this case the constructor would have to be 
immutable).

public immutable int x;

this() immutable
{
    int x = 1;
}

static this() in a class is for initializing class/static variables only, so 
if you did

public static immutable int x;

static this()
{
    int x = 1;
}

that would work. The fact that it is immutable has nothing to do with whether 
it is a member variable or a class/static variable, so it has no effect on 
whether a normal or static constructor is used.

- Jonathan M Davis

teo <teo.ubuntu yahoo.com> writes:

On Mon, 21 Mar 2011 22:27:53 +0100, Simen kjaeraas wrote:

 On Mon, 21 Mar 2011 22:27:17 +0100, teo <teo.ubuntu yahoo.com> wrote:
 
 I cannot initialize immutable class members inside a static this()
 constructor. Is there any reason for that?

 Example:
 class Test
 {
     public immutable(int) x;
     static this()
     {
         x = 1; // Error: variable Test.x can only initialize const x
 inside constructor
     }
 }


 Non-static class members require a this pointer, and thus cannot be
 initialized in a static constructor. However, if that is the error
 message you get, it is clearly misleading.


Yes, that is the message. Thanks for the hint.