On 1/29/16 3:08 PM, Chris Wright wrote:
On Fri, 29 Jan 2016 14:00:08 -0500, Steven Schveighoffer wrote:
On 1/29/16 12:44 PM, Chris Wright wrote:
I want to create an opApply for a type.
I've marked my code @safe, because everything I wrote was @safe. The
body of opApply is @safe, but it calls a delegate that may or may not
be @safe.
How do I make it so I can iterate through this type safely and
systemly?
Likely an overload. Tag the delegate as being @safe or not.
-Steve
That's handy. It works. I can make it so someone can call:
foo.opApply((i, k, v) @safe => 0);
foo.opApply((i, k, v) @system => 0);
And that works.
However, if you have:
@safe void bar() {
foreach(i, k, v; foo) {
}
}
the compiler complains:
opapplysafe.d(12): Error: foo.opApply matches more than one declaration:
opapplysafe.d(2): @safe int(int delegate(int, string, string) @safe
dg)
and:
opapplysafe.d(5): @system int(int delegate(int, string, string)
@system dg)
Guess I'll file a bug.
Definitely seems like a bug.
As a workaround, you can name the opApply functions:
struct S
{
int opApply(int delegate(int, string, string) @safe dg) @safe {...}
int unsafeApply(int delegate(int, string, string) dg) {...}
}
foreach(i, k, v; foo.unsafeApply) {...}
though that's... ugly.
-Steve
