data/stack.hh

   1 # C++ skeleton for Bison
   2
   3 # Copyright (C) 2002-2012 Free Software Foundation, Inc.
   4
   5 # This program is free software: you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation, either version 3 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 m4_pushdef([b4_copyright_years],
  19            [2002-2012])
  20
  21 # We do want M4 expansion after # for CPP macros.
  22 m4_changecom()
  23 m4_divert_push(0)dnl
  24 @output(b4_dir_prefix[]stack.hh@)@
  25 b4_copyright([Stack handling for Bison parsers in C++],
  26              [2002-2012])[
  27
  28 #ifndef BISON_STACK_HH
  29 # define BISON_STACK_HH
  30
  31 # include <deque>
  32
  33 ]b4_namespace_open[
  34   template <class T, class S = std::deque<T> >
  35   class stack
  36   {
  37   public:
  38     // Hide our reversed order.
  39     typedef typename S::reverse_iterator iterator;
  40     typedef typename S::const_reverse_iterator const_iterator;
  41
  42     stack () : seq_ ()
  43     {
  44     }
  45
  46     stack (unsigned int n) : seq_ (n)
  47     {
  48     }
  49
  50     inline
  51     T&
  52     operator [] (unsigned int i)
  53     {
  54       return seq_[i];
  55     }
  56
  57     inline
  58     const T&
  59     operator [] (unsigned int i) const
  60     {
  61       return seq_[i];
  62     }
  63
  64     inline
  65     void
  66     push (const T& t)
  67     {
  68       seq_.push_front (t);
  69     }
  70
  71     inline
  72     void
  73     pop (unsigned int n = 1)
  74     {
  75       for (; n; --n)
  76         seq_.pop_front ();
  77     }
  78
  79     inline
  80     unsigned int
  81     height () const
  82     {
  83       return seq_.size ();
  84     }
  85
  86     inline const_iterator begin () const { return seq_.rbegin (); }
  87     inline const_iterator end () const { return seq_.rend (); }
  88
  89   private:
  90     S seq_;
  91   };
  92
  93   /// Present a slice of the top of a stack.
  94   template <class T, class S = stack<T> >
  95   class slice
  96   {
  97   public:
  98     slice (const S& stack, unsigned int range)
  99       : stack_ (stack)
 100       , range_ (range)
 101     {
 102     }
 103
 104     inline
 105     const T&
 106     operator [] (unsigned int i) const
 107     {
 108       return stack_[range_ - i];
 109     }
 110
 111   private:
 112     const S& stack_;
 113     unsigned int range_;
 114   };
 115 ]b4_namespace_close[
 116
 117 #endif // not BISON_STACK_HH[]dnl
 118 ]
 119 m4_divert_pop(0)
 120 m4_popdef([b4_copyright_years])dnl
 121 m4_changecom([#])