https://issues.dlang.org/show_bug.cgi?id=15623
Issue ID: 15623
Summary: is(M!N) evaluates to true for M!N that fails to
instantiate.
Product: D
Version: D2
Hardware: x86_64
OS: All
Status: NEW
Severity: major
Priority: P1
Component: dmd
Assignee: [email protected]
Reporter: [email protected]
struct HasFoo { void foo() {} }
struct NoFoo {}
struct CallsFoo(T) {
T t;
void bar() { t.foo(); }
}
static assert(is(CallsFoo!HasFoo));
static assert(is(typeof({ alias Baz = CallsFoo!HasFoo; return Baz.init; }())));
static assert(__traits(compiles, { alias Baz = CallsFoo!HasFoo; return
Baz.init; }()));
alias Bar = CallsFoo!HasFoo;
// this should fail:
static assert(is(CallsFoo!NoFoo));
// this should fail too:
static assert(is(typeof({ alias Baz = CallsFoo!NoFoo; return Baz.init; }())));
// this too:
static assert(__traits(compiles, { alias Baz = CallsFoo!NoFoo; return Baz.init;
}()));
// only this fails:
//alias Baz = CallsFoo!NoFoo; // (1)
--
