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+// tree-expr2.h                                      -*- C++ -*-
+/*
+
+Copyright (C) 1992, 1993, 1994, 1995 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, 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+*/
+
+#if !defined (octave_tree_expr2_h)
+#define octave_tree_expr2_h 1
+
+#if defined (__GNUG__)
+#pragma interface
+#endif
+
+class ostream;
+
+class tree_identifier;
+class tree_index_expression;
+class tree_indirect_ref;
+class tree_argument_list;
+
+#include "pt-exp-base.h"
+
+// Prefix expressions.
+
+class
+tree_prefix_expression : public tree_expression
+{
+ public:
+  tree_prefix_expression (int l = -1, int c = -1)
+    : tree_expression (l, c), id (0) { }
+
+  tree_prefix_expression (tree_identifier *t, tree_expression::type et,
+			  int l = -1, int c = -1)
+    : tree_expression (l, c, et), id (t) { }
+
+  ~tree_prefix_expression (void);
+
+  tree_constant eval (int print);
+
+  void eval_error (void);
+
+  int is_prefix_expression (void) const
+    { return 1; }
+
+  char *oper (void) const;
+
+  void print_code (ostream& os);
+
+ private:
+  tree_identifier *id;
+};
+
+// Postfix expressions.
+
+class
+tree_postfix_expression : public tree_expression
+{
+ public:
+  tree_postfix_expression (int l = -1, int c = -1)
+    : tree_expression (l, c), id (0) { }
+
+  tree_postfix_expression (tree_identifier *t, tree_expression::type et,
+			   int l = -1, int c = -1)
+    : tree_expression (l, c, et), id (t) { }
+
+  ~tree_postfix_expression (void);
+
+  tree_constant eval (int print);
+
+  void eval_error (void);
+
+  char *oper (void) const;
+
+  void print_code (ostream& os);
+
+ private:
+  tree_identifier *id;
+};
+
+// Unary expressions.
+
+class
+tree_unary_expression : public tree_expression
+{
+ public:
+  tree_unary_expression (int l = -1, int c = -1)
+    : tree_expression (l, c), op (0) { }
+
+  tree_unary_expression (tree_expression *a, tree_expression::type t,
+			 int l = -1, int c = -1)
+    : tree_expression (l, c, t), op (a) { }
+
+  ~tree_unary_expression (void)
+    { delete op; }
+
+  tree_constant eval (int print);
+
+  void eval_error (void);
+
+  char *oper (void) const;
+
+  void print_code (ostream& os);
+
+ private:
+  tree_expression *op;
+};
+
+// Binary expressions.
+
+class
+tree_binary_expression : public tree_expression
+{
+ public:
+  tree_binary_expression (int l = -1, int c = -1)
+    : tree_expression (l, c), op1 (0), op2 (0) { }
+
+  tree_binary_expression (tree_expression *a, tree_expression *b,
+			  tree_expression::type t, int l = -1, int c = -1)
+    : tree_expression (l, c, t), op1 (a), op2 (b) { }
+
+  ~tree_binary_expression (void)
+    {
+      delete op1;
+      delete op2;
+    }
+
+  tree_constant eval (int print);
+
+  void eval_error (void);
+
+  char *oper (void) const;
+
+  void print_code (ostream& os);
+
+ private:
+  tree_expression *op1;
+  tree_expression *op2;
+};
+
+// Simple assignment expressions.
+
+class
+tree_simple_assignment_expression : public tree_expression
+{
+private:
+  void init (int plhs, int ans_assign)
+    {
+      etype = tree_expression::assignment;
+      lhs_idx_expr = 0;
+      lhs = 0;
+      index = 0;
+      rhs = 0;
+      preserve = plhs;
+      ans_ass = ans_assign;
+    }
+
+ public:
+  tree_simple_assignment_expression (int plhs = 0, int ans_assign = 0,
+				     int l = -1, int c = -1)
+    : tree_expression (l, c)
+      { init (plhs, ans_assign); }
+
+  tree_simple_assignment_expression (tree_identifier *i,
+				     tree_expression *r,
+				     int plhs = 0, int ans_assign = 0,
+				     int l = -1, int c = -1);
+
+  tree_simple_assignment_expression (tree_indirect_ref *i,
+				     tree_expression *r,
+				     int plhs = 0, int ans_assign = 0,
+				     int l = -1, int c = -1)
+    : tree_expression (l, c)
+      {
+	init (plhs, ans_assign);
+	lhs = i;
+	rhs = r;
+      }
+
+  tree_simple_assignment_expression (tree_index_expression *idx_expr,
+				     tree_expression *r,
+				     int plhs = 0, int ans_assign = 0,
+				     int l = -1, int c = -1);
+
+  ~tree_simple_assignment_expression (void);
+
+  int left_hand_side_is_identifier_only (void);
+
+  tree_identifier *left_hand_side_id (void);
+
+  int is_ans_assign (void)
+    { return ans_ass; }
+
+  tree_constant eval (int print);
+
+  int is_assignment_expression (void) const
+    { return 1; }
+
+  void eval_error (void);
+
+  void print_code (ostream& os);
+
+ private:
+  tree_index_expression *lhs_idx_expr;
+  tree_indirect_ref *lhs;
+  tree_argument_list *index;
+  tree_expression *rhs;
+  int preserve;
+  int ans_ass;
+};
+
+// Colon expressions.
+
+class
+tree_colon_expression : public tree_expression
+{
+ public:
+  tree_colon_expression (int l = -1, int c = -1)
+    : tree_expression (l, c, tree_expression::colon),
+      op1(0), op2 (0), op3 (0) { }
+
+  tree_colon_expression (tree_expression *a, tree_expression *b,
+			 int l = -1, int c = -1)
+    : tree_expression (l, c, tree_expression::colon),
+      op1 (a), op2 (b), op3 (0) { }
+
+  ~tree_colon_expression (void)
+    {
+      delete op1;
+      delete op2;
+      delete op3;
+    }
+
+  int is_range_constant (void) const;
+
+  tree_colon_expression *chain (tree_expression *t);
+
+  tree_constant eval (int print);
+
+  void eval_error (const char *s);
+
+  void print_code (ostream& os);
+
+ private:
+  tree_expression *op1;
+  tree_expression *op2;
+  tree_expression *op3;
+};
+
+#endif
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; page-delimiter: "^/\\*" ***
+;;; End: ***
+*/