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digitalmars.D.bugs - [Issue 2200] New: std.string.format behaves wrong when passing an interface reference

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=2200

           Summary: std.string.format behaves wrong when passing an
                    interface reference
           Product: D
           Version: unspecified
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: Phobos
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: 2korden gmail.com


Current std.string.format implementation throws an exception if an interface
reference is passed to it.Although interfaces don't derive from an Object, an
attempt to cast to an Object should be made, and no exception should be thrown
unless the cast was unsuccessful.

*Or* it should be a compile-time error to pass a reference to interface to the
function.

module test;

interface I {}
class C : I {}

C c = new C();
I i = c;
Object o = cast(Object)i;

try { writefln( format(c) ); } catch (Exception e) { writefln(e); }
try { writefln( format(i) ); } catch (Exception e) { writefln("Error: ", e); }
try { writefln( format(o) ); } catch (Exception e) { writefln(e); }

Expected behaviour: "test.C" printed 3 times
Actual behaviour: and exception is thrown while in a format(i);


--
Jul 07 2008
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=2200






Currently writef/writefln fails with compile-time error deep inside std.format
implementation with a "No property toString for test.I" error. It should be
also updated to use cast to Object.

Or, if it is made by design, std.string.format should fail with the same reason
at compile-time.


--
Jul 07 2008
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=2200


dsimcha yahoo.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |DUPLICATE







*** This bug has been marked as a duplicate of 535 ***


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Mar 27 2009