Re: Problem with const correctness

[bearophile]

Gor Gyolchanyan:

I enforce value-type semantics by duplicating the arrays on copy, so it should behave like a value type with no indirections (implicitly convert to

immutable).
What do I need to do for this to work?

This is a first try, not tested much, and I don't know how many
copies it performs:


import std.traits;

struct Array(T) {
     this(T items[]...) {
         this._array = items;
     }

     this(this) {
         static if (isMutable!T)
             this._array = this._array.dup;
         else
             this._array = this._array.idup;
     }

     ref Array opAssign(in Array other) {
         static if (isMutable!T)
             this._array = other._array.dup;
         else
             this._array = other._array.idup;
         return this;
     }

     @property Array!(immutable(T)) idup() {
         return typeof(return)(this._array.idup);
     }

     private T[] _array;
}

void main() {
     auto one = Array!int(1, 2, 3, 4, 5);
     immutable two = one.idup;
}


Bye,
bearophile