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digitalmars.D.learn - Initialise non-copyable, non-default-constrauctable member struct

reply Peter Particle <ParticlePeter gmx.de> writes:
Question is related to this:
https://dlang.org/spec/struct.html#disable_default_construction

struct S {
     int x;
      disable this();     // Disables default construction
      disable this(this); // Disable copying

     this(int v) { x = v; }
}

struct T {
     float y;
     S s;
      disable this();     // Disables default construction
      disable this(this); // Disable copying

     this(float v) {
         y = v;

         s = S(cast(int)v);    // tried option 1
         s.__ctor(cast(int)v); // tried option 2

     }
}

Error: struct `S` is not copyable because it is annotated with 
` disable`
in both cases.

Is there some way around this problem?
Jul 27 2018
parent reply aliak <something something.com> writes:
On Friday, 27 July 2018 at 12:11:37 UTC, Peter Particle wrote:

 Question is related to this:
 https://dlang.org/spec/struct.html#disable_default_construction

 struct S {
     int x;
      disable this();     // Disables default construction
      disable this(this); // Disable copying

     this(int v) { x = v; }
 }

 struct T {
     float y;
     S s;
      disable this();     // Disables default construction
      disable this(this); // Disable copying

     this(float v) {
         y = v;

         s = S(cast(int)v);    // tried option 1
         s.__ctor(cast(int)v); // tried option 2

     }
 }

 Error: struct `S` is not copyable because it is annotated with 
 ` disable`
 in both cases.

 Is there some way around this problem?


This works on the latest dmd:

struct S {
     int x;
      disable this();     // Disables default construction
      disable this(this); // Disable copying

     this(int v) { x = v; }
}

struct T {
     float y;
     S s;
      disable this();     // Disables default construction
      disable this(this); // Disable copying

     this(float v) {
         y = v;
         s = S(cast(int)v);
     }
}

void main() {
     auto s = T(3);
}

https://run.dlang.io/is/lLrUiq
Jul 27 2018
parent reply aliak <something something.com> writes:
On Friday, 27 July 2018 at 13:05:07 UTC, aliak wrote:

 https://run.dlang.io/is/lLrUiq


Sorry: https://run.dlang.io/is/20FUoj
Jul 27 2018
parent Peter Particle <ParticlePeter gmx.de> writes:
On Friday, 27 July 2018 at 13:06:10 UTC, aliak wrote:

 On Friday, 27 July 2018 at 13:05:07 UTC, aliak wrote:

 https://run.dlang.io/is/lLrUiq


 Sorry: https://run.dlang.io/is/20FUoj


Thanks, you are right, but it seems that I have reduced my issue 
too much, as it still does not work with my actual case. I will 
try to properly reduce my code to present my issue. I think that 
the simple example can be fully figured out statically, but my 
case not.
Jul 27 2018