/src/tools/syntax/tree/liberty_ast_expression_binary.e

 1-- This file is part of Liberty Eiffel.
 2--
 3-- Liberty Eiffel is free software: you can redistribute it and/or modify
 4-- it under the terms of the GNU General Public License as published by
 5-- the Free Software Foundation, version 3 of the License.
 6--
 7-- Liberty Eiffel is distributed in the hope that it will be useful,
 8-- but WITHOUT ANY WARRANTY; without even the implied warranty of
 9-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10-- GNU General Public License for more details.
11--
12-- You should have received a copy of the GNU General Public License
13-- along with Liberty Eiffel.  If not, see <http://www.gnu.org/licenses/>.
14--
15deferred class LIBERTY_AST_EXPRESSION_BINARY[E_ -> LIBERTY_AST_NON_TERMINAL_NODE]
16
17inherit
18   LIBERTY_AST_NON_TERMINAL_NODE
19
20feature {LIBERTY_AST_HANDLER}
21   left_expression: E_ is
22      require
23         not is_empty
24         not is_binary
25      do
26         Result ::= nodes.first
27      end
28
29   left_binary: like Current is
30      require
31         not is_empty
32         is_binary
33      do
34         Result ::= nodes.first
35      end
36
37   right_expression: E_ is
38      require
39         not is_empty
40      do
41         Result ::= nodes.last
42      end
43
44   is_binary: BOOLEAN is
45      require
46         not is_empty
47      do
48         Result := nodes.first.name = eiffel_name
49      end
50
51   is_double_operator: BOOLEAN is
52      do
53         Result := count = 4
54      end
55
56   operator1: EIFFEL_IMAGE is
57      local
58         op1: LIBERTY_AST_TERMINAL_NODE
59      do
60         op1 ::= nodes.item(1)
61         Result := op1.image
62      end
63
64   operator2: EIFFEL_IMAGE is
65      require
66         is_double_operator
67      local
68         op2: LIBERTY_AST_TERMINAL_NODE
69      do
70         op2 ::= nodes.item(2)
71         Result := op2.image
72      end
73
74feature {ANY}
75   count: INTEGER is
76      do
77         Result := nodes.count
78      end
79
80feature {}
81   possible_counts: SET[INTEGER] is
82      once
83         Result := {AVL_SET[INTEGER] << 3, 4 >> } -- depends on the operator
84      end
85
86   errors: LIBERTY_ERRORS
87
88end