TokenStreamBasicFilter.cpp

/* ANTLR Translator Generator
 * Project led by Terence Parr at http://www.jGuru.com
 * Software rights: http://www.antlr.org/license.html
 *
 * $Id$
 */
#include "antlr/TokenStreamBasicFilter.hpp"
 
#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
namespace antlr {
#endif
 
/** This object is a TokenStream that passes through all
 *  tokens except for those that you tell it to discard.
 *  There is no buffering of the tokens.
 */
TokenStreamBasicFilter::TokenStreamBasicFilter(TokenStream& input_)
: input(&input_)
{
}
 
void TokenStreamBasicFilter::discard(int ttype)
{
        discardMask.add(ttype);
}
 
void TokenStreamBasicFilter::discard(const BitSet& mask)
{
        discardMask = mask;
}
 
RefToken TokenStreamBasicFilter::nextToken()
{
        RefToken tok = input->nextToken();
        while ( tok && discardMask.member(tok->getType()) ) {
                tok = input->nextToken();
        }
        return tok;
}
 
#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
}
#endif