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digitalmars.D.bugs - [Issue 5723] New: array of base class cannot be initialized with derived types

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5723

           Summary: array of base class cannot be initialized with derived
                    types
           Product: D
           Version: D2
          Platform: x86_64
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: wilfried.kirschenmann gmail.com



2011-03-09 01:04:46 PST ---
Hi, 

The following example



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

void main(string[] args){
    B b;
    C c;
    A[] ar = [b, c];
}

give this error with DMD 2.052 (file is called test.d) :

./test.d(10): Error: cannot implicitly convert expression (b) of type test.A to
test.C
./test.d(10): Error: cannot implicitly convert expression ([(__error),c]) of
type C[] to A[]


Indeed, I agree that b cannot be converted to C.
However, I do not understand why the compiler doesn't try to convert c to A.

As a workaround, I found :
A[] ar = [b, cast(A)c];

In fact, all items except the first one have to be casted. 
The other solution is :
A[] ar = [b];
ar~=[c];

This behavior is inconsistent. I would have expected :
1) all item have to be casted to A
2) no item has to be casted to A
Having just the first element to be implicitly casted is surprising.

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parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5723


Steven Schveighoffer <schveiguy yahoo.com> changed:

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



05:41:07 PST ---


 As a workaround, I found :
 A[] ar = [b, cast(A)c];
 
 In fact, all items except the first one have to be casted. 


No, this is not the case.  You can cast the whole array literal, or you can
cast one element to A (any element will do).

Marking as duplicate.

*** This issue has been marked as a duplicate of issue 5498 ***

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