Re: Proper way to protect (lock) a struct field after initialization ??

[Ali Çehreli via Digitalmars-d-learn]

On 8/8/21 3:11 AM, james.p.leblanc wrote:
Hello All.
Is there a standard way to protect a field of a struct after
the struct has been initialized?

Is this possible with a struct?

If not, I suppose a class (object) would be needed?  If so,
are there any simple pointers to an example of this?

Thanks in advance,

James


I understand your question differently from jfondren. You may be looking 
for a 'const' (or 'immutable') member:

struct S {
  const int i;

  this(int i) {
    // This will work because "first assignment is initialization"
    this.i = i;
  }
}

void main() {
  auto s = S(42);

  // This won't work
  s.i = 43;

  // This won't work either
  s = S(44);
}

Ali