lib/query.cpp

/*
  Query  -  interface for capability queries
 
  Copyright (C)         Lumiera.org
    2008,               Hermann Vosseler <Ichthyostega@web.de>
 
  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation; either version 2 of the
  License, or (at your option) any later version.
 
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
 
  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
* *****************************************************/


#include "lib/query.hpp"
#include "lib/util.hpp"
#include "include/nobugcfg.h"

#include <boost/algorithm/string.hpp>
#include <boost/regex.hpp>
#include <map>

using std::map;
using boost::regex;
using boost::smatch;
using boost::regex_search;
using boost::sregex_iterator;

using util::contains;
using util::isnil;


namespace lumiera
  {
  
  namespace query
    {

    namespace // local definitions
      {
      typedef boost::function<bool(string::value_type)> ChPredicate;
      
      ChPredicate is_alpha = boost::algorithm::is_alpha();    
      ChPredicate is_upper = boost::algorithm::is_upper();    
    } // local defs
    
    
    void
    normalizeID (string& id)
    {
      id = util::sanitize(id);
      if (isnil(id) || !is_alpha (id[0]))
        id.insert(0, "o");
      
      
      REQUIRE (!isnil(id));
      REQUIRE (is_alpha (id[0]));
      
      char first = id[0];
      if (is_upper (first))
        id[0] = std::tolower (first);
    }

    
    
    
    namespace // Implementation details
      {
      map<Symbol, regex> regexTable;
      
      Symbol matchArgument = "\\(\\s*([\\w_\\.\\-]+)\\s*\\),?\\s*"; 
      regex findPredicate (string("(\\w+)")+matchArgument);
      
      inline regex&
      getTermRegex (Symbol sym)
      {
        if (!contains (regexTable, sym))
          regexTable[sym] = regex (string(sym)+=matchArgument);
        return regexTable[sym];
      }
    }
    
    const string
    extractID (Symbol sym, const string& termString)
    {
      smatch match;
      if (regex_search (termString, match, getTermRegex (sym)))
        return (match[1]);
      else
        return "";
    } 
    
    
    const string
    removeTerm (Symbol sym, string& termString)
    {
      smatch match;
      if (regex_search (termString, match, getTermRegex (sym)))
        {
          string res (sym); res += "("+match[1]+")";
          termString.erase (match.position(), match[0].length());
          return res;
        }
      else
        return "";
    } 
  
    
    uint 
    countPraed (const string& q)
    {
      uint cnt (0);
      sregex_iterator end;
      for (sregex_iterator i (q.begin(),q.end(), findPredicate); 
           i != end; ++i)
        ++cnt;
      return cnt;
    }
    
  } // namespace query
    
  
} // namespace lumiera

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