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digitalmars.D.bugs - [Issue 7154] New: [CTFE] failing downcast causes error

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=7154

           Summary: [CTFE] failing downcast causes error
           Product: D
           Version: D2
          Platform: Other
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: maehlvis googlemail.com


--- Comment #0 from Elvis Maehren <maehlvis googlemail.com> 2011-12-22 07:45:40
PST ---
At runtime, a failing downcast evaluates to null.
At compile time, it gives an error:
"Error: cannot reinterpret class from C to test.B at compile time"
It should just evaluate to null, too.

---
class A {}
class B : A {}
class C : A {}

bool test(T)() {
    A a = new T;
    return (cast(B) a) !is null;
}

void main() {
    assert(test!B()); // ok
    assert(!test!C()); // ok
    static assert(test!B()); // ok
    static assert(!test!C()); // error
}
---

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parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=7154


Don <clugdbug yahoo.com.au> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |clugdbug yahoo.com.au
         Resolution|                            |FIXED


--- Comment #1 from Don <clugdbug yahoo.com.au> 2011-12-26 16:03:28 PST ---
https://github.com/D-Programming-Language/dmd/commit/15039d5284922ac673023da65827460972ba60b3

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