On Thu, 04 Aug 2011 11:32:03 +0200, simendsjo <simend...@gmail.com> wrote:
I would like to use a template mixin to add some fields to a struct, but
I'd also like the template to add additional invariant checks without
having to remember to add this for all struct/classes that mixes in this
code.
class C {
int a;
}
mixin template EmbedC() {
C _c;
// oops.. more than one invariant
invariant() {
assert(_c);
}
void close() {
_c = null;
}
}
struct S {
int i = 10;
invariant() {
assert(i >= 10);
}
mixin EmbedC!();
}
void main() {
S s;
s.close();
s._c.a = 10; // access violation, but I want assertion from
invariant
}
What happens if you replace assert(_c) with assert(_c !is null)?