www.digitalmars.com         C & C++   DMDScript  

digitalmars.D.learn - SList and DList init doesn't work in global variable

reply Martin Krejcirik <mk-junk i-line.cz> writes:
Is this intended or known issue ? It works with 2.066.

SList!int gslist = [1,2,3,4,5,6]; // broken since 2.067
// Error: reinterpreting cast from NodeWithoutPayload* to Node* is not
supported in CTFE

DList!int gdlist = [1,2,3,4,5,6]; // broken since 2.067
// Error: non-constant expression ...

void main()
{
    SList!int lslist = [1,2,3,4,5,6]; // OK
    DList!int ldlist = [1,2,3,4,5,6]; // OK
}

-- 
mk
Sep 28 2015
parent =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 09/28/2015 02:15 PM, Martin Krejcirik wrote:

 Is this intended or known issue ? It works with 2.066.

 SList!int gslist = [1,2,3,4,5,6]; // broken since 2.067
 // Error: reinterpreting cast from NodeWithoutPayload* to Node* is not
 supported in CTFE

 DList!int gdlist = [1,2,3,4,5,6]; // broken since 2.067
 // Error: non-constant expression ...

 void main()
 {
      SList!int lslist = [1,2,3,4,5,6]; // OK
      DList!int ldlist = [1,2,3,4,5,6]; // OK
 }


Yes, it looks like there are problems with their implementations. Those 
questions aside, I would initialize such module variables in a module 
static this() anyway:

import std.container;

SList!int gslist;
DList!int gdlist;

static this() {
     gslist = [1,2,3,4,5,6];
     gdlist = [1,2,3,4,5,6];
}

void main() {
}

If you want the lists to be immutable, then the following initialization 
pattern works:

import std.container;

immutable SList!int gslist;
immutable DList!int gdlist;

auto init_gslist()
{
     return SList!int([1,2,3,4,5,6]);
}

auto init_gd_list()
{
     return DList!int([1,2,3,4,5,6]);
}

static this() {
     gslist = init_gslist();
     gdlist = init_gd_list();
}

void main() {
}

The fact that I needed the two module-level init_* functions is also 
problematic, right? For example, moving those inside static this() does 
not work.

Ali
Sep 28 2015