src/WordList.cpp

   1 /**
   2  * \file WordList.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Stefan Schimanski
   7  *
   8  * Full author contact details are available in file CREDITS.
   9  */
  10
  11 #include <config.h>
  12
  13 #include "WordList.h"
  14
  15 #include "support/convert.h"
  16 #include "support/debug.h"
  17 #include "support/docstring.h"
  18 #include "support/weighted_btree.h"
  19
  20 #include "support/lassert.h"
  21
  22 namespace lyx {
  23
  24 ///
  25 WordList theGlobalWordList;
  26
  27 WordList & theWordList()
  28 {
  29         return theGlobalWordList;
  30 }
  31
  32 ///
  33 struct WordList::Impl {
  34         ///
  35         size_t c_;
  36         ///
  37         typedef stx::weighted_btree<docstring, size_t, int> Words;
  38         ///
  39         Words words_;
  40 };
  41
  42
  43 WordList::WordList()
  44 {
  45         d = new Impl;
  46         d->c_ = 0;
  47
  48 #if 0
  49         for (size_t i = 1000000; i > 0; --i) {
  50                 d->words_.insert("a" + convert<docstring>(i), size_t(1), stx::Void());
  51         }
  52 #endif
  53 }
  54
  55
  56 WordList::~WordList()
  57 {
  58         delete d;
  59 }
  60
  61
  62 docstring const & WordList::word(size_t idx) const
  63 {
  64         Impl::Words::const_iterator it = d->words_.find_summed_weight(idx);
  65         LASSERT(it != d->words_.end(), /**/);
  66
  67         // We use the key() method here, and not something like it->first
  68         // because the btree only returns (iterator-) temporary value pairs.
  69         // If we returned the first component of those here, we get an
  70         // invalid reference and therefore strange crashes.
  71         return it.key();
  72 }
  73
  74
  75 size_t WordList::size() const
  76 {
  77         return d->words_.summed_weight();
  78 }
  79
  80
  81 void WordList::insert(docstring const & w)
  82 {
  83         Impl::Words::iterator it = d->words_.find(w);
  84         if (it == d->words_.end())
  85                 d->words_.insert(w, size_t(1), 1);
  86         else {
  87                 it.data()++;
  88                 d->words_.change_weight(it, 1);
  89         }
  90 }
  91
  92
  93 void WordList::remove(docstring const & w)
  94 {
  95         Impl::Words::iterator it = d->words_.find(w);
  96         if (it != d->words_.end()) {
  97                 it.data()--;
  98                 d->words_.change_weight(it, 0);
  99                 // We will not erase here, but instead we just leave it
 100                 // in the btree with weight 0. This avoid too much
 101                 // reorganisation of the tree all the time.
 102                 //if (it.data() == 0)
 103                 //      d->words_.erase(w);
 104         }
 105 }
 106
 107 } // namespace lyx