On 03/08/2012 08:49 PM, H. S. Teoh wrote:
On Thu, Mar 08, 2012 at 08:22:05PM +0100, Timon Gehr wrote:
On 03/08/2012 08:09 PM, H. S. Teoh wrote:
[...]
The problem is, how to write this function so that it can be called from
*both* a const public method and a non-const public method? Since the
method itself doesn't actually modify anything, it *should* in theory be
possible to mark it as const:
const Slot *findSlot(Key key) { ... }
However, because the const applies to 'this', the compiler insists that
referencing anything via 'this', including reading a pointer to a slot,
must also be const, so it refuses to let the return type be Slot*; it
has to be const(Slot)*.
But this is silly, because now the caller isn't allowed to modify the
Slot either, so now I need to bloat the code with two identical copies
of findSlot, one with const, and one without (since if it wasn't marked
const, then a const method couldn't call it).
[...]
inout(Slot)* findSlot(Key key) inout { ... }
Ahhh. Thanks!
But that still doesn't solve the problem:
inout(Slot)* findSlot(Key key) inout {
auto slot = slots[hash(key)];
inout(Slot)* slot = slots[hash(key)];
while (slot) {
if (slot.hash == hash(key)&& slot.key == key)
return slot;
// Error: cannot modify inout(Slot)*
---> slot = slot.next;
}
return null;
}
T
