Re: Boost Spirit and VS2017

On Tue, Oct 30, 2018 at 6:57 PM Michael Powell <[email protected]> wrote:
>
> Hello,
>
> I am receiving the following error building against the latest VS2017 ...
>
> 1>Version_Parser.cpp
> 1>d:\dev\boost.org\boost_1_68_0\boost\iostreams\positioning.hpp(96):
> error C4996: 'std::fpos<_Mbstatet>::seekpos': warning STL4019: The
> member std::fpos::seekpos() is non-Standard, and is preserved only for
> compatibility with workarounds for old versions of Visual C++. It will
> be removed in a future release, and in this release always returns 0.
> Please use standards-conforming mechanisms to manipulate fpos, such as
> conversions to and from streamoff, or an integral type, instead. If
> you are receiving this message while compiling Boost.IOStreams, a fix
> has been submitted upstream to make Boost use standards-conforming
> mechanisms, as it does for other compilers. You can define
> _SILENCE_FPOS_SEEKPOS_DEPRECATION_WARNING to acknowledge that you have
> received this warning, or define _REMOVE_FPOS_SEEKPOS to remove
> std::fpos::seekpos entirely.
> 1>c:\program files (x86)\microsoft visual
> studio\2017\enterprise\vc\tools\msvc\14.15.26726\include\iosfwd(59):
> note: see declaration of 'std::fpos<_Mbstatet>::seekpos'

I got past this issue. Thanks go to Gavin on the Boost list! Still
need to acknowledge with the definition however.

> With my grammar:
>
> BOOST_FUSION_ADAPT_STRUCT(NS_VERSION_H::version, _major, _minor,
> _patch, _build);
>
> template <typename It>
> struct version_parser : qi::grammar<It, NS_VERSION_H::version()> {
>
>     version_parser() : dot_('.'), version_parser::base_type(_start) {
>         using qi::lit;
>         using qi::hold;
>         using qi::short_;
>         _major_part = short_;
>         _minor_part = lit(dot_) >> short_;
>         _patch_part = lit(dot_) >> short_;
>         _build_part = lit(dot_) >> short_;
>         _start = hold[_major_part >> _minor_part >> -(_patch_part >>
> -_build_part)];
>     }
>
> private:
>
>     qi::rule<It, NS_VERSION_H::version()> _start;
>     const char dot_;
>     qi::rule<It, short()> _major_part;
>     qi::rule<It, short()> _minor_part;
>     qi::rule<It, short()> _patch_part;
>     qi::rule<It, short()> _build_part;
> };
>
> bool try_parse_version(const std::string& s, NS_VERSION_H::version& v) {
>     using It = std::string::const_iterator;
>     using qi::parse;
>
>     It first = s.begin(), last = s.end();
>
>     if (!parse(first, last, version_parser<It>{}, v)) {
>         std::cout << "Failed to parse: '" << s << "'" << std::endl;
>         return false;
>     }
>
>     const auto dot_ = ".";
>
>     std::cout << "version: "
>         << v._major
>         << dot_ << v._minor
>         << dot_ << v._patch
>         << dot_ << v._build << std::endl;
>
>     return true;
> }

It seems to be parsing all but the last element. I think it's an EOI
issue? But memory escapes me at the moment how Spirit Qi handles that
use case... Something like this?

        using qi::lit;
        using qi::no_skip;
        using qi::short_;
        using qi::eoi;
        _major_part = short_;
        _minor_part = lit(dot_) >> short_;
        _patch_part = lit(dot_) >> short_;
        _build_part = lit(dot_) >> short_;
        _start = no_skip[_major_part >> _minor_part >> (_patch_part |
(_patch_part >> _build_part))] >> eoi;

Cheers!

> At present I have not furnished any Spirit flags or anything of that
> sort; pretty much taking the includes, grammar, building as-is.
>
> Secondary to the error, I want the parser to reject spaces, should
> just be numeric (short) and the dot delimiter.
>
> Best regards,
>
> Michael Powell