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
  27 #ifndef BISON_STACK_HH
  28 # define BISON_STACK_HH
  29
  30 #include <deque>
  31
  32 ]b4_namespace_open[
  33   template <class T, class S = std::deque<T> >
  34   class stack
  35   {
  36   public:
  37     // Hide our reversed order.
  38     typedef typename S::reverse_iterator iterator;
  39     typedef typename S::const_reverse_iterator const_iterator;
  40
  41     stack ()
  42       : seq_ ()
  43     {
  44     }
  45
  46     stack (unsigned int n)
  47       : seq_ (n)
  48     {
  49     }
  50
  51     inline
  52     T&
  53     operator [] (unsigned int i)
  54     {
  55       return seq_[i];
  56     }
  57
  58     inline
  59     const T&
  60     operator [] (unsigned int i) const
  61     {
  62       return seq_[i];
  63     }
  64
  65     inline
  66     void
  67     push (const T& t)
  68     {
  69       seq_.push_front (t);
  70     }
  71
  72     inline
  73     void
  74     pop (unsigned int n = 1)
  75     {
  76       for (; n; --n)
  77         seq_.pop_front ();
  78     }
  79
  80     inline
  81     typename S::size_type
  82     size () const
  83     {
  84       return seq_.size ();
  85     }
  86
  87     inline
  88     const_iterator
  89     begin () const
  90     {
  91       return seq_.rbegin ();
  92     }
  93
  94     inline
  95     const_iterator
  96     end () const
  97     {
  98       return seq_.rend ();
  99     }
 100
 101   private:
 102     /// The wrapped container.
 103     S seq_;
 104   };
 105
 106   /// Present a slice of the top of a stack.
 107   template <class T, class S = stack<T> >
 108   class slice
 109   {
 110   public:
 111     slice (const S& stack, unsigned int range)
 112       : stack_ (stack),
 113         range_ (range)
 114     {
 115     }
 116
 117     inline
 118     const T&
 119     operator [] (unsigned int i) const
 120     {
 121       return stack_[range_ - i];
 122     }
 123
 124   private:
 125     const S& stack_;
 126     unsigned int range_;
 127   };
 128 ]b4_namespace_close[
 129
 130 #endif // not BISON_STACK_HH[]dnl
 131 ]
 132 m4_divert_pop(0)
 133 m4_popdef([b4_copyright_years])dnl
 134 m4_changecom([#])