On 06/16/2012 07:19 AM, Bernard Helyer wrote:
On Friday, 15 June 2012 at 12:56:49 UTC, Timon Gehr wrote:
On 06/15/2012 02:19 PM, bearophile wrote:
Timon Gehr:
Why not allow equality operators to operate on types?
That's nice, of course. But is it possible?
Yes, certainly.
Not without losing the context insensitivity of the D grammar (because
now we can't say for certain what "T == J" is
It is a comparison. That suffices for the parser. The grammar stays
completely context-independent.
until we semantically
understand the program, but as it is now we understand it as comparing
two values).
As it is now we don't know what it will do.
import some.other.module;
S a, b;
bool c = a == b;
///////
module some.other.module
struct S{ bool opEquals(){ hardDrive.format(); assert(0); } }
That's a big thing to throw away,
T[2] foo;
auto b = foo[1]; // is this legal?
and this doesn't justify the change.
-Bernard.
I don't think this argument is valid.
