diff options
author | Patrick Simianer <p@simianer.de> | 2011-10-20 02:31:25 +0200 |
---|---|---|
committer | Patrick Simianer <p@simianer.de> | 2011-10-20 02:31:25 +0200 |
commit | a5a92ebe23c5819ed104313426012011e32539da (patch) | |
tree | 3416818c758d5ece4e71fe522c571e75ea04f100 /klm/util/tokenize_piece.hh | |
parent | b88332caac2cbe737c99b8098813f868ca876d8b (diff) | |
parent | 78baccbb4231bb84a456702d4f574f8e601a8182 (diff) |
finalized merge
Diffstat (limited to 'klm/util/tokenize_piece.hh')
-rw-r--r-- | klm/util/tokenize_piece.hh | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/klm/util/tokenize_piece.hh b/klm/util/tokenize_piece.hh new file mode 100644 index 00000000..ee1c7ab2 --- /dev/null +++ b/klm/util/tokenize_piece.hh @@ -0,0 +1,69 @@ +#ifndef UTIL_TOKENIZE_PIECE__ +#define UTIL_TOKENIZE_PIECE__ + +#include "util/string_piece.hh" + +#include <boost/iterator/iterator_facade.hpp> + +/* Usage: + * + * for (PieceIterator<' '> i(" foo \r\n bar "); i; ++i) { + * std::cout << *i << "\n"; + * } + * + */ + +namespace util { + +// Tokenize a StringPiece using an iterator interface. boost::tokenizer doesn't work with StringPiece. +template <char d> class PieceIterator : public boost::iterator_facade<PieceIterator<d>, const StringPiece, boost::forward_traversal_tag> { + public: + // Default construct is end, which is also accessed by kEndPieceIterator; + PieceIterator() {} + + explicit PieceIterator(const StringPiece &str) + : after_(str) { + increment(); + } + + bool operator!() const { + return after_.data() == 0; + } + operator bool() const { + return after_.data() != 0; + } + + static PieceIterator<d> end() { + return PieceIterator<d>(); + } + + private: + friend class boost::iterator_core_access; + + void increment() { + const char *start = after_.data(); + for (; (start != after_.data() + after_.size()) && (d == *start); ++start) {} + if (start == after_.data() + after_.size()) { + // End condition. + after_.clear(); + return; + } + const char *finish = start; + for (; (finish != after_.data() + after_.size()) && (d != *finish); ++finish) {} + current_ = StringPiece(start, finish - start); + after_ = StringPiece(finish, after_.data() + after_.size() - finish); + } + + bool equal(const PieceIterator &other) const { + return after_.data() == other.after_.data(); + } + + const StringPiece &dereference() const { return current_; } + + StringPiece current_; + StringPiece after_; +}; + +} // namespace util + +#endif // UTIL_TOKENIZE_PIECE__ |