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diff --git a/src/include/fst/extensions/far/far.h b/src/include/fst/extensions/far/far.h
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+++ b/src/include/fst/extensions/far/far.h
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+// far.h
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2005-2010 Google, Inc.
+// Author: riley@google.com (Michael Riley)
+//
+// \file
+// Finite-State Transducer (FST) archive classes.
+//
+
+#ifndef FST_EXTENSIONS_FAR_FAR_H__
+#define FST_EXTENSIONS_FAR_FAR_H__
+
+#include <fst/extensions/far/stlist.h>
+#include <fst/extensions/far/sttable.h>
+#include <fst/fst.h>
+#include <fst/vector-fst.h>
+
+namespace fst {
+
+enum FarEntryType { FET_LINE, FET_FILE };
+enum FarTokenType { FTT_SYMBOL, FTT_BYTE, FTT_UTF8 };
+
+// FST archive header class
+class FarHeader {
+ public:
+  const string &FarType() const { return fartype_; }
+  const string &ArcType() const { return arctype_; }
+
+  bool Read(const string &filename) {
+    FstHeader fsthdr;
+    if (filename.empty()) {  // Header reading unsupported on stdin.
+      return false;
+    } else if (IsSTTable(filename)) {  // Check if STTable
+      ReadSTTableHeader(filename, &fsthdr);
+      fartype_ = "sttable";
+      arctype_ = fsthdr.ArcType().empty() ? "unknown" : fsthdr.ArcType();
+      return true;
+    } else if (IsSTList(filename)) {  // Check if STList
+      ReadSTListHeader(filename, &fsthdr);
+      fartype_ = "sttable";
+      arctype_ = fsthdr.ArcType().empty() ? "unknown" : fsthdr.ArcType();
+      return true;
+    }
+    return false;
+  }
+
+ private:
+  string fartype_;
+  string arctype_;
+};
+
+enum FarType { FAR_DEFAULT = 0, FAR_STTABLE = 1, FAR_STLIST = 2,
+               FAR_SSTABLE = 3 };
+
+// This class creates an archive of FSTs.
+template <class A>
+class FarWriter {
+ public:
+  typedef A Arc;
+
+  // Creates a new (empty) FST archive; returns NULL on error.
+  static FarWriter *Create(const string &filename, FarType type = FAR_DEFAULT);
+
+  // Adds an FST to the end of an archive. Keys must be non-empty and
+  // in lexicographic order. FSTs must have a suitable write method.
+  virtual void Add(const string &key, const Fst<A> &fst) = 0;
+
+  virtual FarType Type() const = 0;
+
+  virtual bool Error() const = 0;
+
+  virtual ~FarWriter() {}
+
+ protected:
+  FarWriter() {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(FarWriter);
+};
+
+
+// This class iterates through an existing archive of FSTs.
+template <class A>
+class FarReader {
+ public:
+ typedef A Arc;
+
+  // Opens an existing FST archive in a single file; returns NULL on error.
+  // Sets current position to the beginning of the achive.
+  static FarReader *Open(const string &filename);
+
+  // Opens an existing FST archive in multiple files; returns NULL on error.
+  // Sets current position to the beginning of the achive.
+  static FarReader *Open(const vector<string> &filenames);
+
+  // Resets current posision to beginning of archive.
+  virtual void Reset() = 0;
+
+  // Sets current position to first entry >= key.  Returns true if a match.
+  virtual bool Find(const string &key) = 0;
+
+  // Current position at end of archive?
+  virtual bool Done() const = 0;
+
+  // Move current position to next FST.
+  virtual void Next() = 0;
+
+  // Returns key at the current position. This reference is invalidated if
+  // the current position in the archive is changed.
+  virtual const string &GetKey() const = 0;
+
+  // Returns FST at the current position. This reference is invalidated if
+  // the current position in the archive is changed.
+  virtual const Fst<A> &GetFst() const = 0;
+
+  virtual FarType Type() const = 0;
+
+  virtual bool Error() const = 0;
+
+  virtual ~FarReader() {}
+
+ protected:
+  FarReader() {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(FarReader);
+};
+
+
+template <class A>
+class FstWriter {
+ public:
+  void operator()(ostream &strm, const Fst<A> &fst) const {
+    fst.Write(strm, FstWriteOptions());
+  }
+};
+
+
+template <class A>
+class STTableFarWriter : public FarWriter<A> {
+ public:
+  typedef A Arc;
+
+  static STTableFarWriter *Create(const string filename) {
+    STTableWriter<Fst<A>, FstWriter<A> > *writer =
+        STTableWriter<Fst<A>, FstWriter<A> >::Create(filename);
+    return new STTableFarWriter(writer);
+  }
+
+  void Add(const string &key, const Fst<A> &fst) { writer_->Add(key, fst); }
+
+  FarType Type() const { return FAR_STTABLE; }
+
+  bool Error() const { return writer_->Error(); }
+
+  ~STTableFarWriter() { delete writer_; }
+
+ private:
+  explicit STTableFarWriter(STTableWriter<Fst<A>, FstWriter<A> > *writer)
+      : writer_(writer) {}
+
+ private:
+  STTableWriter<Fst<A>, FstWriter<A> > *writer_;
+
+  DISALLOW_COPY_AND_ASSIGN(STTableFarWriter);
+};
+
+
+template <class A>
+class STListFarWriter : public FarWriter<A> {
+ public:
+  typedef A Arc;
+
+  static STListFarWriter *Create(const string filename) {
+    STListWriter<Fst<A>, FstWriter<A> > *writer =
+        STListWriter<Fst<A>, FstWriter<A> >::Create(filename);
+    return new STListFarWriter(writer);
+  }
+
+  void Add(const string &key, const Fst<A> &fst) { writer_->Add(key, fst); }
+
+  FarType Type() const { return FAR_STLIST; }
+
+  bool Error() const { return writer_->Error(); }
+
+  ~STListFarWriter() { delete writer_; }
+
+ private:
+  explicit STListFarWriter(STListWriter<Fst<A>, FstWriter<A> > *writer)
+      : writer_(writer) {}
+
+ private:
+  STListWriter<Fst<A>, FstWriter<A> > *writer_;
+
+  DISALLOW_COPY_AND_ASSIGN(STListFarWriter);
+};
+
+
+template <class A>
+FarWriter<A> *FarWriter<A>::Create(const string &filename, FarType type) {
+  switch(type) {
+    case FAR_DEFAULT:
+      if (filename.empty())
+        return STListFarWriter<A>::Create(filename);
+    case FAR_STTABLE:
+      return STTableFarWriter<A>::Create(filename);
+      break;
+    case FAR_STLIST:
+      return STListFarWriter<A>::Create(filename);
+      break;
+    default:
+      LOG(ERROR) << "FarWriter::Create: unknown far type";
+      return 0;
+  }
+}
+
+
+template <class A>
+class FstReader {
+ public:
+  Fst<A> *operator()(istream &strm) const {
+    return Fst<A>::Read(strm, FstReadOptions());
+  }
+};
+
+
+template <class A>
+class STTableFarReader : public FarReader<A> {
+ public:
+  typedef A Arc;
+
+  static STTableFarReader *Open(const string &filename) {
+    STTableReader<Fst<A>, FstReader<A> > *reader =
+        STTableReader<Fst<A>, FstReader<A> >::Open(filename);
+    // TODO: error check
+    return new STTableFarReader(reader);
+  }
+
+  static STTableFarReader *Open(const vector<string> &filenames) {
+    STTableReader<Fst<A>, FstReader<A> > *reader =
+        STTableReader<Fst<A>, FstReader<A> >::Open(filenames);
+    // TODO: error check
+    return new STTableFarReader(reader);
+  }
+
+  void Reset() { reader_->Reset(); }
+
+  bool Find(const string &key) { return reader_->Find(key); }
+
+  bool Done() const { return reader_->Done(); }
+
+  void Next() { return reader_->Next(); }
+
+  const string &GetKey() const { return reader_->GetKey(); }
+
+  const Fst<A> &GetFst() const { return reader_->GetEntry(); }
+
+  FarType Type() const { return FAR_STTABLE; }
+
+  bool Error() const { return reader_->Error(); }
+
+  ~STTableFarReader() { delete reader_; }
+
+ private:
+  explicit STTableFarReader(STTableReader<Fst<A>, FstReader<A> > *reader)
+      : reader_(reader) {}
+
+ private:
+  STTableReader<Fst<A>, FstReader<A> > *reader_;
+
+  DISALLOW_COPY_AND_ASSIGN(STTableFarReader);
+};
+
+
+template <class A>
+class STListFarReader : public FarReader<A> {
+ public:
+  typedef A Arc;
+
+  static STListFarReader *Open(const string &filename) {
+    STListReader<Fst<A>, FstReader<A> > *reader =
+        STListReader<Fst<A>, FstReader<A> >::Open(filename);
+    // TODO: error check
+    return new STListFarReader(reader);
+  }
+
+  static STListFarReader *Open(const vector<string> &filenames) {
+    STListReader<Fst<A>, FstReader<A> > *reader =
+        STListReader<Fst<A>, FstReader<A> >::Open(filenames);
+    // TODO: error check
+    return new STListFarReader(reader);
+  }
+
+  void Reset() { reader_->Reset(); }
+
+  bool Find(const string &key) { return reader_->Find(key); }
+
+  bool Done() const { return reader_->Done(); }
+
+  void Next() { return reader_->Next(); }
+
+  const string &GetKey() const { return reader_->GetKey(); }
+
+  const Fst<A> &GetFst() const { return reader_->GetEntry(); }
+
+  FarType Type() const { return FAR_STLIST; }
+
+  bool Error() const { return reader_->Error(); }
+
+  ~STListFarReader() { delete reader_; }
+
+ private:
+  explicit STListFarReader(STListReader<Fst<A>, FstReader<A> > *reader)
+      : reader_(reader) {}
+
+ private:
+  STListReader<Fst<A>, FstReader<A> > *reader_;
+
+  DISALLOW_COPY_AND_ASSIGN(STListFarReader);
+};
+
+
+template <class A>
+FarReader<A> *FarReader<A>::Open(const string &filename) {
+  if (filename.empty())
+    return STListFarReader<A>::Open(filename);
+  else if (IsSTTable(filename))
+    return STTableFarReader<A>::Open(filename);
+  else if (IsSTList(filename))
+    return STListFarReader<A>::Open(filename);
+  return 0;
+}
+
+
+template <class A>
+FarReader<A> *FarReader<A>::Open(const vector<string> &filenames) {
+  if (!filenames.empty() && filenames[0].empty())
+    return STListFarReader<A>::Open(filenames);
+  else if (!filenames.empty() && IsSTTable(filenames[0]))
+    return STTableFarReader<A>::Open(filenames);
+  else if (!filenames.empty() && IsSTList(filenames[0]))
+    return STListFarReader<A>::Open(filenames);
+  return 0;
+}
+
+}  // namespace fst
+
+#endif  // FST_EXTENSIONS_FAR_FAR_H__