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digitalmars.D.bugs - [Issue 5609] New: struct opEquals doesn't conform to language specifications.

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5609

           Summary: struct opEquals doesn't conform to language
                    specifications.
           Product: D
           Version: D2
          Platform: x86_64
               URL: http://www.digitalmars.com/d/2.0/operatoroverloading.h
                    tml#equals
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: eatingstaples gmail.com


--- Comment #0 from eatingstaples gmail.com 2011-02-18 04:09:28 PST ---
Created an attachment (id=916)
Code demonstrating the issue.

The language specification states (with respect to opEquals in structs) "...the
expressions a.opEquals(b) and b.opEquals(a) are tried. If both resolve to the
same opEquals function, then the expression is rewritten to be a.opEquals(b).
If one is a better match then the other, or one compiles and the other does
not, the one is selected.
Otherwise, an error results."

Structs, however, don't properly follow the "if one compiles and the other does
not" rule, at least not for the form a.opEquals(rvalue). Example attached.

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Feb 18 2011
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5609


kennytm gmail.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dpx.infinity gmail.com


--- Comment #1 from kennytm gmail.com 2011-05-11 10:40:22 PDT ---
*** Issue 5979 has been marked as a duplicate of this issue. ***

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May 11 2011
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=5609


SomeDude <lovelydear mailmetrash.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |lovelydear mailmetrash.com


--- Comment #2 from SomeDude <lovelydear mailmetrash.com> 2012-04-22 16:23:34
PDT ---
Code in the attachment:

struct A
{
    int x;

    A foo()
    {
        return A(x);
    }

    const bool opEquals(ref const A other)
    {
        return (x == other.x);
    }
}

void main()
{
    auto a = A(5);
    assert(a.foo == a); // OK
    assert(a == a.foo); // Error
}

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