Workarounds for Lack of Mutable Keyword

[Craig Black]

"Robert Fraser" <fraserofthenight at gmail.com> wrote in message 
news:ft1r7d$1q0b$1 at digitalmars.com...
> Craig Black wrote:
>> I did it and it was very easy.  I didn't know you could cast away const 
>> so easily in D.  This works for const, but not invariant.  Since we have 
>> the ability to subvert const so easily, there should be no problem living 
>> without mutable fields.
>>
>> import std.stdio;
>>
>> void ConstAssign(T)(ref const T x, T y) { *cast(T*)&x = y; }
>>
>> class A
>> {
>> public:
>>  int x;
>>  int y;
>>  void setY(int ny) const { ConstAssign(y, ny); }
>> }
>>
>> void foo(const A a) { a.setY(2); }
>>
>> int main(char[][] args)
>> {
>>  A a = new A;
>>  a.y = 1;
>>  foo(a);
>>  writefln(a.y);
>>  return 0;
>> }
>
> ight, but be sure to synchronize for multi threaded access.

In the case that I'm thinking of using this for, I know multiple threads 
won't be contending for the "mutable" fields.

-Craig