Re: [boost] hex/unhex()?

Subject: Re: [boost] hex/unhex()?
From: Hartmut Kaiser (hartmut.kaiser_at_[hidden])
Date: 2011-11-02 07:54:21

> On Wed, Nov 2, 2011 at 12:32 PM, Hartmut Kaiser <hartmut.kaiser_at_[hidden]>
> wrote:
> > As Marshal pointed out, Spirit supports that easily:
> >
> >    std::string input("61626f6465");
> >    std::string str;
> >    if (qi::parse(input.begin(), input.end(), qi::hex, str))
> >        assert(str == "abode");
> 
> Is there no range-based variant of parse()?
> 
> > and
> >
> >    std::string str("abode");
> >    std::string output;
> >    if (karma::generate(back_inserter(output), karma::hex, str))
> >        assert(output == "61626f6465");
> >
> > If you want to avoid the cost of possible reallocations in output, just
> call output.reserve(...) upfront. Otherwise both code snippets generate
> code equivalent to hand written assembly and have been shown to be as fast
> as it can get.
> 
> When would generate() fail (return false)?
> AFAIK to hex can't fail and in that case a variant that returns
> std::string would be nicer.

Actually, please disregard what I wrote, it is complete nonsense. I misread
your initial mail.

Note to self: drink coffee before responding to email!

Regards Hartmut
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