On Thursday, 29 September 2016 at 12:28:54 UTC, Tomer Filiba
wrote:
Consider this code
struct MyTable {
bool opBinaryRight(string op: "in")(int x) {
return true;
}
}
Now let's use it:
MyTable m1;
assert(5 in m1);
Everything works as expected. Now suppose I had a const object
object
const MyTable m2;
5 in m2; // Error: rvalue of in expression must be an
associative array, not const(MyTable)
A super-cryptic error message. First of all, "in expressions"
are not limited to associative arrays. Second, the error makes
me think I didn't implement the operator -- but I did.
Indeed, please someone has to fix this !
Instead, supposed I had a `contains` method instead,
m2.contains(5); // Error: mutable method
dtest.MyTable.contains is not callable using a const object
I also think that "mutable method" means anything. If the meaning
is that the method can change the object state then "muting
method" would be better.
Which is the real error, of course, the one I would have hoped
to get in the first place. My code was templated and got a `T
table`, so it was nearly impossible to guess that `T` was
actually `const MyTable`
I understand operators go through rewriting rules, but it's
nearly impossible to understand what's wrong with code with
such errors.
-tomer
