如何在 boost::circular 缓冲区上使用 boost::regex？

Question

我正在 boost::circular_buffer 中捕获数据，现在想对内容执行正则表达式搜索，但我在 boost::regex 理解如何查看缓冲区时遇到了一些困难.

这是我想根据示例 here:

做的那种事情的精简版

    // Set up a pre-populated data buffer as an example
    std::string test = "Fli<usefuldata>bble";
    boost::circular_buffer<char> dataBuff;
    for (std::string::iterator it = test.begin(); it != test.end(); ++it)
    {
        dataBuff.push_back(*it);
    }

    // Set up the regex
    static const boost::regex e("<\w*>");
    std::string::const_iterator start, end;
    start = dataBuff.begin(); // <-- error C2679
    end = dataBuff.end();
    boost::match_flag_type flags = boost::match_default;

    // Try and find something of interest in the buffer
    boost::match_results<std::string::const_iterator> what;
    if (regex_search(start, end, what, e, flags))
    {
        // Do something - we found what we're after...
    }

我（我认为这是可以理解的）在尝试编译时遇到此错误：

1>c:\projects\ProtocolBufferProcessor\ProtocolBufferProcessor.h(53): error C2679: binary '=' : no operator found which takes a right-hand operand of type 'boost::cb_details::iterator<Buff,Traits>' (or there is no acceptable conversion)
1>          with
1>          [
1>              Buff=boost::circular_buffer<char>,
1>              Traits=boost::cb_details::nonconst_traits<std::allocator<char>>
1>          ]
1>          c:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\include\xstring(435): could be 'std::_String_iterator<_Elem,_Traits,_Alloc> &std::_String_iterator<_Elem,_Traits,_Alloc>::operator =(const std::_String_iterator<_Elem,_Traits,_Alloc> &)'
1>          with
1>          [
1>              _Elem=char,
1>              _Traits=std::char_traits<char>,
1>              _Alloc=std::allocator<char>
1>          ]
1>          while trying to match the argument list '(std::_String_iterator<_Elem,_Traits,_Alloc>, boost::cb_details::iterator<Buff,Traits>)'
1>          with
1>          [
1>              _Elem=char,
1>              _Traits=std::char_traits<char>,
1>              _Alloc=std::allocator<char>
1>          ]
1>          and
1>          [
1>              Buff=boost::circular_buffer<char>,
1>              Traits=boost::cb_details::nonconst_traits<std::allocator<char>>
1>          ]

...但是除了每次我运行正则表达式时从循环缓冲区逐个字符地创建一个 std::string 之外，我还能做些什么吗？

我使用的是 Boost v1.54，如果有区别的话。

Answer 1

您需要使用缓冲区的迭代器类型：

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#include <boost/circular_buffer.hpp>
#include <boost/regex.hpp>

using buffer_t = boost::circular_buffer<char>;

int main() {
    // Set up a pre-populated data buffer as an example
    std::string test = "Fli<usefuldata>bble";
    buffer_t dataBuff;
    for (std::string::iterator it = test.begin(); it != test.end(); ++it)
    {
        dataBuff.push_back(*it);
    }

    // Set up the regex
    static const boost::regex e("<\w*>");

    buffer_t::const_iterator start = dataBuff.begin(); // <-- error C2679
    buffer_t::const_iterator end = dataBuff.end();
    boost::match_flag_type flags = boost::match_default;

    // Try and find something of interest in the buffer
    boost::match_results<buffer_t::const_iterator> what;
    if (regex_search(start, end, what, e, flags))
    {
        // Do something - we found what we're after...
    }
}

如何在 boost::circular 缓冲区上使用 boost::regex？

How can I use boost::regex on a boost::circular buffer?

c++

boost

boost-regex

boost-circularbuffer