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Subject: Re: [boost] Curiousity question
From: Edward Diener (eldiener_at_[hidden])
Date: 2016-10-31 00:24:38

On 10/30/2016 7:44 PM, Gavin Lambert wrote:
> On 30/10/2016 07:34, Edward Diener wrote:
>> What I gathered from my original OP from everyone's response is that
>> either:
>> 1) Programmers would rather hard-code a choice of using a Boost library
>> or its C++ standard library equivalent in their code based on whether
>> their code was meant to be used for C++11 or above or not
>> or
>> 2) Roll their own hand-made system for choosing based on their
>> individual needs
>> rather than use a library like cxx_dual which automatically makes the
>> choice of whether to use a Boost library or its C++ standard equivalent
>> based on what is available at compile time.
> FWIW, I think that's mostly due to unfamiliarity with the library, and
> not an indication that more people wouldn't have used it had they been
> aware of it.

I have announced the availability of cxx_dual for all 3 releases of it.
I did get the impression on the first announcement that some programmers
had looked at it, but I have rarely received the impression that anyone
has actually tried it. I say that because there has been very little
discussion about the technical areas of the library.

> Although as the std and Boost implementations are not identical in many
> respects, having code switch from one to another based on environment
> might make people nervous, unless they feel "in control" of the
> switching mechanism and can adjust its choices.

The documentation explains how to control the algorithm which chooses
between the Boost or C++ standard for any dual library or for all dual
libraries. This occurs in the section entitled " Overriding the default
choosing algorithm" online at

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