Re: [Boost-users] operator<< for std::vector< boost::variant< type_a, type_b >>

Subject: Re: [Boost-users] operator<< for std::vector< boost::variant< type_a, type_b >>
From: Michael Powell (mwpowellhtx_at_[hidden])
Date: 2018-06-18 21:34:26

On Mon, Jun 18, 2018 at 5:22 PM, Maarten Verhage via Boost-users
<boost-users_at_[hidden]> wrote:
>
> ----- Original Message -----
> From: "Michael Powell via Boost-users" <boost-users_at_[hidden]>
> To: <boost-users_at_[hidden]>
> Cc: "Michael Powell" <mwpowellhtx_at_[hidden]>
> Sent: Monday, June 18, 2018 23:00
> Subject: Re: [Boost-users] operator<< for std::vector< boost::variant<
> type_a, type_b >>
>
>
>> On Mon, Jun 18, 2018 at 4:51 PM, Chris Cleeland via Boost-users
>> <boost-users_at_[hidden]> wrote:
>>>
>>>
>>> On Mon, Jun 18, 2018 at 3:20 PM Maarten Verhage via Boost-users
>>> <boost-users_at_[hidden]> wrote:
>>>>
>>>>
>>>>
>>>> boost::variant is obviously part of boost. And the compiler error is
>>>> pointing in a variant header. So I'm pretty confident "Boost users" in
>>>> the
>>>> appropriate mailing list for this issue.
>>>
>>>
>>> Except for the fact that it's not.  I looked at the code, and I suspect
>>> you've ended up confusing yourself.
>>>
>>> In particular, your typedefs are confusing.  Are you sure you didn't mean
>>> this?  It looks like you did based on the rest of the code.
>>>
>>> typedef boost::variant< int, double > parameter_t;
>>> typedef std::vector< parameter_t > employee_t;
>
> I'm actually pursuing this tree-like hierarchy. I might even need to make it
> recursive. But I want to start easy.
>
> typedef std::vector< boost::variant< int, double >> parameter_t;
> typedef std::vector< boost::variant< int, double, parameter_t >> employee_t;
>
> Have you looked into the stackoverflow answer by: Richard Hodges? The poster
> had the same compiler error and the solution Richard presented is
> significantly more complicated than a single operator<< overload.

To be perfectly clear, I'm not sure what you're fishing for here, and
I am definitely not here to analyze nor troubleshoot your code. But,
there did seem to be at least a general question about operator
overloading. What you do with that knowledge in your specific case is
entirely up to you. I'm not at liberty to discuss beyond that.

>>> In other words, a vector (type `employee_t`) where each element is a
>>> variant
>>> of either `int` or `double`.
>>>
>>> If that's what you meant to type, then compiling with clang++ -std=c++14
>>> creates an a.out that prints "306000" as expected.
>>>
>>>>
>>>>
>>>> You know, I sense some resentment against me. Can you clarify please?
>>>
>>>
>>> I didn't.  In fact, he answered your question by giving you references to
>>> documentation based on the error message you presented.  Unfortunately I
>>> think that error message was a red herring.
>>
>> Glad to help. Consider it on the table, rule it out if it isn't useful
>> to you, or in this case helps to narrow the root cause, or whatever.
>> Completely up to you.
>>
>>>> If you opened the attachment you can see I'm already at that level. And
>>>> according to the stackoverflow answer for a very much related issue the
>>>> solution is some next level stuff.
>>>
>>>
>>> Fortunately, I suspect that the solution really just involves fixing your
>>> types.
>>>
>>> --
>>> Chris Cleeland
>>>
>>> _______________________________________________
>>> Boost-users mailing list
>>> Boost-users_at_[hidden]
>>> https://lists.boost.org/mailman/listinfo.cgi/boost-users
>>>
>> _______________________________________________
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>
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