Hi,<div>I am new to using boost and am trying to learn basics so I can use regex features in my code.</div><div>In my test program, I want a function to simply extract some numbers that follow after a certain string pattern and then to read those numbers into a vector.</div>
<div><br></div><div>This is an outline of what i would like to do:</div><div><br></div><div><div>// function definition</div><div>#ifndef findnumbers.h</div><div>#define findnumbers.h</div><div><br></div><div>#include &lt;string&gt;</div>
<div>#include &lt;fstream&gt;</div><div>#include &lt;vector&gt;</div><div>#include &lt;boost/regex.hpp&gt;</div></div><div>#endif</div><div><br></div><div>void findnumbers (ifstream&amp; afile)</div><div>{</div><div>// assume file is opened in main - i have passed a reference</div>
<div>boost::regex expression ( ....having trouble with this);</div><div>// search for matches - there will be a fixed number of numbers e.g 10</div><div>std::string const_iterator start, end;</div><div>start = afile.begin( );</div>
<div>end = afile.end( );</div><div>std::vector&lt;int&gt; results;</div><div>boost::match_results&lt;std::vector&lt;int&gt;::const_iterator&gt; what;</div><div>for(int count = 0; count !=10; count++)</div><div>{</div><div>
boost::regex_search(start,end,what,expression)</div><div>{</div><div>//if a number is found place in the vector</div><div>results.push_back(count);</div><div>}</div><div><br></div><div>So the first problem I have is defining a correct expression. The pattern has the format &quot;sometext&gt;NUMBERS&lt;sometext&quot; newline. The NUMBERS may be one or two digits combined and the pattern is repeated 10 times. I have searched the archives and tried to build something based on the examples I have read, but cannot seem to find a working solution. Can anyone help please in defining an expression?</div>
<div><br></div><div>I do not need a solution to my function overall as I should be able to write it correctly once I know how to define the pattern.</div><div><br></div><div>Kind regards  </div><div><br></div><div><br></div>
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