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diff --git a/klm/lm/model.hh b/klm/lm/model.hh
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+#ifndef LM_MODEL__
+#define LM_MODEL__
+
+#include "lm/binary_format.hh"
+#include "lm/config.hh"
+#include "lm/facade.hh"
+#include "lm/search_hashed.hh"
+#include "lm/search_trie.hh"
+#include "lm/vocab.hh"
+#include "lm/weights.hh"
+
+#include <algorithm>
+#include <vector>
+
+namespace util { class FilePiece; }
+
+namespace lm {
+namespace ngram {
+
+// If you need higher order, change this and recompile.  
+// Having this limit means that State can be
+// (kMaxOrder - 1) * sizeof(float) bytes instead of
+// sizeof(float*) + (kMaxOrder - 1) * sizeof(float) + malloc overhead
+const std::size_t kMaxOrder = 6;
+
+// This is a POD.  
+class State {
+  public:
+    bool operator==(const State &other) const {
+      if (valid_length_ != other.valid_length_) return false;
+      const WordIndex *end = history_ + valid_length_;
+      for (const WordIndex *first = history_, *second = other.history_;
+          first != end; ++first, ++second) {
+        if (*first != *second) return false;
+      }
+      // If the histories are equal, so are the backoffs.  
+      return true;
+    }
+
+    // You shouldn't need to touch anything below this line, but the members are public so FullState will qualify as a POD.  
+    // This order minimizes total size of the struct if WordIndex is 64 bit, float is 32 bit, and alignment of 64 bit integers is 64 bit.  
+    WordIndex history_[kMaxOrder - 1];
+    float backoff_[kMaxOrder - 1];
+    unsigned char valid_length_;
+};
+
+size_t hash_value(const State &state);
+
+namespace detail {
+
+// Should return the same results as SRI.  
+// Why VocabularyT instead of just Vocabulary?  ModelFacade defines Vocabulary.  
+template <class Search, class VocabularyT> class GenericModel : public base::ModelFacade<GenericModel<Search, VocabularyT>, State, VocabularyT> {
+  private:
+    typedef base::ModelFacade<GenericModel<Search, VocabularyT>, State, VocabularyT> P;
+  public:
+    // Get the size of memory that will be mapped given ngram counts.  This
+    // does not include small non-mapped control structures, such as this class
+    // itself.  
+    static size_t Size(const std::vector<uint64_t> &counts, const Config &config = Config());
+
+    GenericModel(const char *file, const Config &config = Config());
+
+    FullScoreReturn FullScore(const State &in_state, const WordIndex new_word, State &out_state) const;
+
+    /* Slower call without in_state.  Don't use this if you can avoid it.  This
+     * is mostly a hack for Hieu to integrate it into Moses which sometimes
+     * forgets LM state (i.e. it doesn't store it with the phrase).  Sigh.   
+     * The context indices should be in an array.  
+     * If context_rbegin != context_rend then *context_rbegin is the word
+     * before new_word.  
+     */
+    FullScoreReturn FullScoreForgotState(const WordIndex *context_rbegin, const WordIndex *context_rend, const WordIndex new_word, State &out_state) const;
+
+    /* Get the state for a context.  Don't use this if you can avoid it.  Use
+     * BeginSentenceState or EmptyContextState and extend from those.  If
+     * you're only going to use this state to call FullScore once, use
+     * FullScoreForgotState. */
+    void GetState(const WordIndex *context_rbegin, const WordIndex *context_rend, State &out_state) const;
+
+  private:
+    friend void LoadLM<>(const char *file, const Config &config, GenericModel<Search, VocabularyT> &to);
+
+    float SlowBackoffLookup(const WordIndex *const context_rbegin, const WordIndex *const context_rend, unsigned char start) const;
+
+    FullScoreReturn ScoreExceptBackoff(const WordIndex *context_rbegin, const WordIndex *context_rend, const WordIndex new_word, unsigned char &backoff_start, State &out_state) const;
+
+    // Appears after Size in the cc file.
+    void SetupMemory(void *start, const std::vector<uint64_t> &counts, const Config &config);
+
+    void InitializeFromBinary(void *start, const Parameters &params, const Config &config, int fd);
+
+    void InitializeFromARPA(const char *file, util::FilePiece &f, void *start, const Parameters &params, const Config &config);
+
+    Backing &MutableBacking() { return backing_; }
+
+    static const ModelType kModelType = Search::kModelType;
+
+    Backing backing_;
+    
+    VocabularyT vocab_;
+
+    typedef typename Search::Unigram Unigram;
+    typedef typename Search::Middle Middle;
+    typedef typename Search::Longest Longest;
+
+    Search search_;
+};
+
+} // namespace detail
+
+// These must also be instantiated in the cc file.  
+typedef ::lm::ngram::ProbingVocabulary Vocabulary;
+typedef detail::GenericModel<detail::ProbingHashedSearch, Vocabulary> ProbingModel;
+// Default implementation.  No real reason for it to be the default.  
+typedef ProbingModel Model;
+
+typedef ::lm::ngram::SortedVocabulary SortedVocabulary;
+typedef detail::GenericModel<detail::SortedHashedSearch, SortedVocabulary> SortedModel;
+
+typedef detail::GenericModel<trie::TrieSearch, SortedVocabulary> TrieModel;
+
+} // namespace ngram
+} // namespace lm
+
+#endif // LM_MODEL__