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digitalmars.D.bugs - [Issue 6028] New: Cannot implicitly convert an array of class to an array of interface

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=6028

           Summary: Cannot implicitly convert an array of class to an
                    array of interface
           Product: D
           Version: D2
          Platform: Other
        OS/Version: Mac OS X
            Status: NEW
          Keywords: rejects-valid
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: kennytm gmail.com



Test case:

----------------------------
interface X {}
class K : X {}
class L : K {}

void main() {
    L[] x;
    K[] y = x;  // ok
    X[] z = y;  // error
} 
----------------------------
test.d(8): Error: cannot implicitly convert expression (y) of type K[] to X[]
----------------------------

It should be possible to implicitly convert an array of class to an array of
(one of) its base interface type.

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parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=6028


Steven Schveighoffer <schveiguy yahoo.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |schveiguy yahoo.com
         Resolution|                            |INVALID



10:13:59 PDT ---
Actually, you shouldn't be able to convert either.

See issue 2095

Though converting from a class array to an interface array is even worse -- an
interface reference is not the same address of a class reference.  So this
implicit cast would not only have to rewrite all the elements, it would corrupt
the original array.

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