Thread overview
BitArray in custom class & initialize it in ctor with arguments
Mar 22, 2014
MarisaLovesUsAll
Mar 22, 2014
bearophile
Mar 23, 2014
MarisaLovesUsAll
March 22, 2014
Hi! I need to use array of bits in my custom class. I tried to
add std.bitmanip.BitArray as field, but got a strange error. What
am I doing wrong?

import std.bitmanip;
class Scene
{
     BitArray collisionMap;
     this(int w, int h)
     {
         collisionMap.init([0,0,0]);
     }
}

C:\D\dmd2\windows\bin\..\..\src\phobos\std\bitmanip.d
line 606
Error: btr cannot be interpreted at compile time, because it has
no available source code


If I use collisionMap.length(w*h), I get:

C:\D\dmd2\windows\bin\..\..\src\phobos\std\bitmanip.d
line 554
Error: non-constant expression [0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u,
0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u,
0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u,
0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u,
0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u,
0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u,
0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u,
0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u, 0u,


And if I use BitArray in default ctor ( this() ), or in other
function in class, or in main function, all is OK. But I need
only ctor with arguments that initialize the BitArray with '0'
and sets 'w*h' length.

DMD version 2.065.0

Sorry for bad English.
March 22, 2014
MarisaLovesUsAll:

> Hi! I need to use array of bits in my custom class. I tried to
> add std.bitmanip.BitArray as field, but got a strange error. What
> am I doing wrong?
>
> import std.bitmanip;
> class Scene
> {
>      BitArray collisionMap;
>      this(int w, int h)
>      {
>          collisionMap.init([0,0,0]);
>      }
> }
>
> C:\D\dmd2\windows\bin\..\..\src\phobos\std\bitmanip.d
> line 606
> Error: btr cannot be interpreted at compile time, because it has
> no available source code

To me this program compiles:


import std.bitmanip;

class Scene {
     BitArray collisionMap;
     this(int w, int h) {
         collisionMap.init([0,0,0]);
     }
}
void main() {}


Errors like "btr cannot be interpreted at compile time" mean that you are trying to run at compile-time something that can only run at run-time. So are you using enums or static immutables or static constructors or something like that?

Bye,
bearophile
March 23, 2014
On Saturday, 22 March 2014 at 10:02:39 UTC, bearophile wrote:
> MarisaLovesUsAll:
>
>> Hi! I need to use array of bits in my custom class. I tried to
>> add std.bitmanip.BitArray as field, but got a strange error. What
>> am I doing wrong?
>>
>> import std.bitmanip;
>> class Scene
>> {
>>     BitArray collisionMap;
>>     this(int w, int h)
>>     {
>>         collisionMap.init([0,0,0]);
>>     }
>> }
>>
>> C:\D\dmd2\windows\bin\..\..\src\phobos\std\bitmanip.d
>> line 606
>> Error: btr cannot be interpreted at compile time, because it has
>> no available source code
>
> To me this program compiles:
>
>
> import std.bitmanip;
>
> class Scene {
>      BitArray collisionMap;
>      this(int w, int h) {
>          collisionMap.init([0,0,0]);
>      }
> }
> void main() {}
>
>
> Errors like "btr cannot be interpreted at compile time" mean that you are trying to run at compile-time something that can only run at run-time. So are you using enums or static immutables or static constructors or something like that?
>
> Bye,
> bearophile

Thanks for help! It was static(?) ctor, I had been trying to create Scene from another class via
class App
{
    Scene scene = new Scene(13,10);
}