https://issues.dlang.org/show_bug.cgi?id=23272

johanengelen@weka.io changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |industry, rejects-valid

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https://issues.dlang.org/show_bug.cgi?id=23272

--- Comment #1 from johanengelen@weka.io ---
Workaround is to use `is` instead of `==`.

(`assert (s.caseOfTemplated!(a => typeid(a)) is typeid(string));`)

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https://issues.dlang.org/show_bug.cgi?id=23272

Iain Buclaw <ibuclaw@gdcproject.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ibuclaw@gdcproject.org
          Component|dmd                         |druntime

--- Comment #2 from Iain Buclaw <ibuclaw@gdcproject.org> ---
This is not a compiler regression.

Introduced by: https://github.com/dlang/druntime/pull/3665

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https://issues.dlang.org/show_bug.cgi?id=23272

--- Comment #3 from Iain Buclaw <ibuclaw@gdcproject.org> ---
Possible reduction of the original.
---
alias AliasSeq(TList...) = TList;

template EnumMembers(E)
{
    alias EnumMembers = AliasSeq;
    static foreach (M; __traits(allMembers, E))
        EnumMembers = AliasSeq!(__traits(getMember, E, M));
}

struct SumType(Ts)
{
    mixin(() {
        auto s = "enum Cases : ubyte {";
        return s ~= "unset}\n";
    }());

    Cases which;
    union {
        Ts cases;
    }
}

auto caseOfTemplated(alias func, T)(T s) {
    final switch (s.which) foreach(CASE; EnumMembers!(T.Cases)) {
        case CASE:
            return func(s.cases);
    }
}


void foo() {
    bool validate() {
        SumType!(int) s;
        caseOfTemplated!(a => typeid(a))(s) == typeid(string);
        return true;
    }
    static assert(validate);
}

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https://issues.dlang.org/show_bug.cgi?id=23272

Adam D. Ruppe <destructionator@gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |destructionator@gmail.com

--- Comment #4 from Adam D. Ruppe <destructionator@gmail.com> ---
The code that does it is:

// to bypass any opCast that may be present on the original class.
        return .opEquals!(Object, Object)(*cast(Object*) &lhs, *cast(Object*)
&rhs);


And appears plain `cast() lhs, cast() rhs` instead of the pointer cast will
also bypass opCast so i think this is a fairly easy fix.

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https://issues.dlang.org/show_bug.cgi?id=23272

Dlang Bot <dlang-bot@dlang.rocks> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |pull

--- Comment #5 from Dlang Bot <dlang-bot@dlang.rocks> ---
@schveiguy created dlang/dmd pull request #14726 "fix 23272. CTFE comparison of TypeInfo fails" fixing this issue:

- fix 23272. CTFE comparison of TypeInfo fails

https://github.com/dlang/dmd/pull/14726

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https://issues.dlang.org/show_bug.cgi?id=23272

--- Comment #6 from Iain Buclaw <ibuclaw@gdcproject.org> ---
(In reply to Iain Buclaw from comment #3)
> Possible reduction of the original.
Which can be hand simplified further to:
---
struct SumType
{
    int cases;
}

auto caseOfTemplated(alias func, T)(T s)
{
    return func(s.cases);
}

void foo()
{
    auto validate()
    {
        SumType s;
        auto t = caseOfTemplated!(a => typeid(a))(s) == typeid(string);
        return true;
    }
    static assert(validate);
}

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https://issues.dlang.org/show_bug.cgi?id=23272

--- Comment #7 from Iain Buclaw <ibuclaw@gdcproject.org> ---
(In reply to Iain Buclaw from comment #6)
> (In reply to Iain Buclaw from comment #3)
> > Possible reduction of the original.
> Which can be hand simplified further to:
Oh wait, I'm being an idiot.
---
void foo()
{
    auto validate()
    {
        assert(typeid(int) != typeid(string));
        return true;
    }
    static assert(validate);
}

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