Is there a function which searches for an array of words by taking the array as an arbitrary parameter like boost::regex_search in boost library?

Question

I need to implement a search mechanism for a list of words and give the result whether the word is found are not in a text provided.

I implemented this using boost library. And it is as follows,

int main(int argc, char**argv)
{
   int count = argc - 2;
   std::string text = argv[1];
   for(int i = 2; i < argc; i++)
   {
      boost::regex re(argv[i], boost::regex::icase);
      if(boost::regex_search(text, re))
      {
          std::cout<<re<<" Found in "<<text<<std::endl;
          count--;
      }
      else std::cout<<re<<" Not Found in " <<text<<std::endl;
   }
   if(count == 0)
   {
      std::cout <<"ALL WORDS ARE FOUND"<<std::endl;
   }
   else std::cout << "SOME WORDS ARE NOT FOUND"<<std::endl;
}

It is working fine for the command line arguements.

Now, what I need is I should provide an array of words directly to the boost search method (if any is available) as a parameter which should return whether all words are found are not.

I've Googled for this but of no use.

Why are you using regex? It seems to me like string::find() would work fine (http://en.cppreference.com/w/cpp/string/basic_string/find). — Nasser Al-Shawwa, Jul 21 '14 at 11:14
@sehe I know. I was commenting on OP's implementation, but I missed the `boost::regex::icase` part. What I was suggesting is that `find()` would give the same result as the implementation. Anyway, my bad. — Nasser Al-Shawwa, Jul 21 '14 at 11:17
@Nasser, from huge program which uses `boost` methods, I copied only a part which actually uses `regex_search`. — Shiva Kumar Ganthi, Jul 21 '14 at 11:25
@Nasser you try that when arg[3] contains `"Ha.*!"`. And `text` contains `"Handsome Hallelujah Hazards!"`. `icase` is a mere detail here. Regex has vastly different semantics than `find` (which is probably why there are entire libraries implement regex search) — sehe, Jul 21 '14 at 11:44

score 1 · Accepted Answer · answered Jul 21 '14 at 11:19

1

Either just use an array:

 std::vector<std::string> arr { "many", "words", "in", "array" };
 int count = arr.size();

 std::string text = argv[1];
 for(std::string const& word : arr)
 {
    boost::regex re(text, boost::regex::icase);
    if(boost::regex_search(text, re))
    {
        std::cout<<re<<" Found in "<<text<<std::endl;
        count--;
    }
    else std::cout<<re<<" Not Found in " <<text<<std::endl;
 }

You could make a regular expression containing all the words you are looking for (this would (vastly) reduce runtime complexity, but makes it harder to count the presence of individual words).

answered Jul 21 '14 at 11:19

sehe

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Since you are using initializer lists, I presume that you are working with C++11, in which case I would suggest that you add some information about `std::regex` to OP – Nasser Al-Shawwa Jul 21 '14 at 11:21
@sehe, Thanks for your answer. But, I need a boost library function which directly takes `arr` as a parameter and returns me the output as `FOUND` or `Not Found`. – Shiva Kumar Ganthi Jul 21 '14 at 11:22
3

@Nasser std::regex is still widely unimplemented (at least GCC<4.9). I've no interest in suggesting less-supported, less featured (standard) libraries, when the OP is simply using Boost. – sehe Jul 21 '14 at 11:30
2

@ShivaKumarGanthi I need a function that I can call with arbitrary parameters and returns Unicorns. (Hint: _there is no silver bullet_; boost is a highly generic library and contains building blocks. You can be almost certain that Boost Regex functions do no take arrays as arguments anyways, so I think that's end of story then). – sehe Jul 21 '14 at 11:32
@sehe If there is no function which takes an array as an _arbitrary paramater_ then it is okay! – Shiva Kumar Ganthi Jul 21 '14 at 11:37

Is there a function which searches for an array of words by taking the array as an arbitrary parameter like boost::regex_search in boost library?

1 Answers1