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#ifndef UTIL_TOKENIZE_PIECE__
#define UTIL_TOKENIZE_PIECE__
#include "util/string_piece.hh"
#include <boost/iterator/iterator_facade.hpp>
#include <algorithm>
#include <iostream>
/* 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_;
};
class MultiCharacter {
public:
explicit MultiCharacter(const StringPiece &delimiter) : delimiter_(delimiter) {}
StringPiece Find(const StringPiece &in) const {
return StringPiece(std::search(in.data(), in.data() + in.size(), delimiter_.data(), delimiter_.data() + delimiter_.size()), delimiter_.size());
}
private:
StringPiece delimiter_;
};
class AnyCharacter {
public:
explicit AnyCharacter(const StringPiece &chars) : chars_(chars) {}
StringPiece Find(const StringPiece &in) const {
return StringPiece(std::find_first_of(in.data(), in.data() + in.size(), chars_.data(), chars_.data() + chars_.size()), 1);
}
private:
StringPiece chars_;
};
template <class Find, bool SkipEmpty = false> class TokenIter : public boost::iterator_facade<TokenIter<Find, SkipEmpty>, const StringPiece, boost::forward_traversal_tag> {
public:
TokenIter() {}
TokenIter(const StringPiece &str, const Find &finder) : after_(str), finder_(finder) {
increment();
}
bool operator!() const {
return current_.data() == 0;
}
operator bool() const {
return current_.data() != 0;
}
static TokenIter<Find> end() {
return TokenIter<Find>();
}
private:
friend class boost::iterator_core_access;
void increment() {
do {
StringPiece found(finder_.Find(after_));
current_ = StringPiece(after_.data(), found.data() - after_.data());
if (found.data() == after_.data() + after_.size()) {
after_ = StringPiece(NULL, 0);
} else {
after_ = StringPiece(found.data() + found.size(), after_.data() - found.data() + after_.size() - found.size());
}
} while (SkipEmpty && current_.data() && current_.empty()); // Compiler should optimize this away if SkipEmpty is false.
}
bool equal(const TokenIter<Find> &other) const {
return after_.data() == other.after_.data();
}
const StringPiece &dereference() const {
return current_;
}
StringPiece current_;
StringPiece after_;
Find finder_;
};
} // namespace util
#endif // UTIL_TOKENIZE_PIECE__
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