• via Digitalmars-d-bugs (49/49) Feb 05 2015 https://issues.dlang.org/show_bug.cgi?id=14128

via Digitalmars-d-bugs <digitalmars-d-bugs puremagic.com> writes:

https://issues.dlang.org/show_bug.cgi?id=14128

          Issue ID: 14128
           Summary: wrong alias
           Product: D
           Version: D1 & D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: major
          Priority: P1
         Component: DMD
          Assignee: nobody puremagic.com
          Reporter: vlevenfeld gmail.com

The line "alias b = that.object" seems to alias this.object:


struct TrivialFunctor (T)
{
    T object;

    int opCmp ()(auto ref TrivialFunctor!T that)
    {
        alias a = this.object;
        alias b = that.object;

        import std.stdio;
        writeln (this.object, ` < `, that.object); // 1 < 2
        writeln (a, ` < `, b); // 1 < 1
        writeln (&(this.object) == &(that.object)); // false, ok
        writeln (&a == &b); // true?!
        stdout.flush;

        if (a < b)
            return -1;
        else if (a > b)
            return 1;
        else return 0;
    }

    auto opBinary (string op)(auto ref TrivialFunctor!T that)
    {
        return TrivialFunctor (mixin(q{this.object } ~ op ~ q{ that.object}));
    }
}
auto trivial_functor (T)(T value)
{
    return TrivialFunctor!T (value);
}

void main ()
{
    TrivialFunctor!int a = 1.trivial_functor, b = 2.trivial_functor;

    auto c = a + b;

    assert (a < b && b < c); // fails
}

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