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+// variables.h                                              -*- C++ -*-
+/*
+
+Copyright (C) 1992, 1993 John W. Eaton
+
+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 2, 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, write to the Free
+Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#if !defined (_variables_h)
+#define _variables_h 1
+
+#ifdef __GNUG__
+#pragma interface
+#endif
+
+class istream;
+class symbol_record;
+class symbol_table;
+class tree;
+class tree_constant;
+
+extern int symbol_out_of_date (symbol_record *sr);
+extern symbol_record *force_global (char *name);
+extern int bind_variable (char *, tree_constant *);
+extern int bind_protected_variable (char *, tree_constant *);
+extern char *octave_string_variable (char *);
+extern int octave_real_scalar_variable (char *, double&);
+extern int extract_keyword (istream&, char *, char *);
+extern int extract_keyword (istream&, char *, int&);
+extern void skip_comments (istream&);
+extern int valid_identifier (char *);
+extern int identifier_exists (char *);
+extern tree *is_valid_function (tree_constant&, char *, int warn = 0);
+extern int takes_correct_nargs (tree *, int, char *, int warn = 0);
+extern char **make_name_list (void);
+
+// Symbol table for symbols at the top level.
+extern symbol_table *top_level_sym_tab;
+
+// Symbol table for the current scope.
+extern symbol_table *curr_sym_tab;
+
+// Symbol table for global symbols.
+extern symbol_table *global_sym_tab;
+
+#endif
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; page-delimiter: "^/\\*" ***
+;;; End: ***
+*/