std regex_search to match only current line

Question

I use a various regexes to parse a C source file, line by line. First i read all the content of file in a string:

ifstream file_stream(\"commented.cpp\",ifstream         


        

Answer 1

If it is not what you want please comment so I will delete the answer

What you are doing is not a correct way of using a regex library.
Thus here is my suggestion for anyone that wants to use std::regex library.

1. It only supports ECMAScript that somehow is a little poor than all modern regex library.

2. It has bugs as many as you like ( just I found ):

   1. the same regex but different results on Linux and Windows only C++
   2. std::regex and ignoring flags
   3. std::regex_match and lazy quantifier with strange behavior

3. In some cases (I test specifically with std::match_results ) It is 200 times slower in comparison to std.regex in d language

4. It has very confusing flag-match and almost it does not work (at least for me)

conclusion: do not use it at all.

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But if anyone still demands to use c++ anyway then you can:

1. use boost::regex ^{about Boost library} because:

   1. It is PCRE support
   2. It has less bug ( I have not seen any )
   3. It is smaller in bin file ( I mean executable file after compiling )
   4. It is faster then std::regex

2. use gcc version 7.1.0 and NOT below. The last bug I found is in version 6.3.0

3. use clang version 3 or above

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If you have enticed (= persuade) to NOT use c++ then you can use:

1. Use d regular expression ^link library for large task: std.regex and why:

   1. Fast ^{Faster Command Line Tools in D}
   2. Easy
   3. Flexible ^drn

2. Use native pcre or pcre2 ^link that have been written in c

   • Extremely fast but a little complicated
3. Use perl for a simple task and specially Perl one-liner ^link