view libinterp/parse-tree/pt-colon.h @ 30833:449e26c26b41 stable

new is_colon_expression predicate for parse tree expression objects * pt-exp.h (is_colon_expression): New virtual function. * pt-colon.h (is_colon_expression): New function.
author John W. Eaton <jwe@octave.org>
date Mon, 07 Mar 2022 15:02:34 -0500
parents 796f54d4ddbf
children e88a07dec498
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////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 1996-2022 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Octave is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if ! defined (octave_pt_colon_h)
#define octave_pt_colon_h 1

#include "octave-config.h"

#include <string>

class octave_value;
class octave_value_list;

#include "pt-exp.h"
#include "pt-walk.h"

namespace octave
{
  class symbol_scope;

  // Colon expressions.

  class tree_colon_expression : public tree_expression
  {
  public:

    tree_colon_expression (int l = -1, int c = -1)
      : tree_expression (l, c), m_base (nullptr), m_limit (nullptr),
        m_increment (nullptr), m_save_base (false) { }

    tree_colon_expression (tree_expression *bas, tree_expression *lim,
                           int l = -1, int c = -1)
      : tree_expression (l, c), m_base (bas), m_limit (lim),
        m_increment (nullptr), m_save_base (false) { }

    tree_colon_expression (tree_expression *bas, tree_expression *lim,
                           tree_expression *inc, int l = -1, int c = -1)
      : tree_expression (l, c), m_base (bas), m_limit (lim),
        m_increment (inc), m_save_base (false) { }

    // No copying!

    tree_colon_expression (const tree_colon_expression&) = delete;

    tree_colon_expression& operator = (const tree_colon_expression&) = delete;

    ~tree_colon_expression (void)
    {
      if (! m_save_base)
        delete m_base;

      delete m_limit;
      delete m_increment;
    }

    void preserve_base (void) { m_save_base = true; }

    bool rvalue_ok (void) const { return true; }

    void eval_error (const std::string& s) const;

    tree_expression * base (void) { return m_base; }

    tree_expression * limit (void) { return m_limit; }

    tree_expression * increment (void) { return m_increment; }

    tree_expression * dup (symbol_scope& scope) const;

    bool is_colon_expression (void) const { return true; }

    octave_value evaluate (tree_evaluator&, int nargout = 1);

    octave_value_list evaluate_n (tree_evaluator& tw, int nargout = 1)
    {
      return ovl (evaluate (tw, nargout));
    }

    void accept (tree_walker& tw)
    {
      tw.visit_colon_expression (*this);
    }

  private:

    // The components of the expression.
    tree_expression *m_base;
    tree_expression *m_limit;
    tree_expression *m_increment;

    bool m_save_base;
  };
}

#endif