Statistics
| Revision:

root / intl / eval-plural.h @ 1

History | View | Annotate | Download (2.71 KB)

1
/* Plural expression evaluation.
2
   Copyright (C) 2000-2003 Free Software Foundation, Inc.
3

4
   This program is free software; you can redistribute it and/or modify it
5
   under the terms of the GNU Library General Public License as published
6
   by the Free Software Foundation; either version 2, or (at your option)
7
   any later version.
8

9
   This program is distributed in the hope that it will be useful,
10
   but WITHOUT ANY WARRANTY; without even the implied warranty of
11
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12
   Library General Public License for more details.
13

14
   You should have received a copy of the GNU Library General Public
15
   License along with this program; if not, write to the Free Software
16
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
17
   USA.  */
18

    
19
#ifndef STATIC
20
#define STATIC static
21
#endif
22

    
23
/* Evaluate the plural expression and return an index value.  */
24
STATIC
25
unsigned long int
26
internal_function
27
plural_eval (struct expression *pexp, unsigned long int n)
28
{
29
  switch (pexp->nargs)
30
    {
31
    case 0:
32
      switch (pexp->operation)
33
        {
34
        case var:
35
          return n;
36
        case num:
37
          return pexp->val.num;
38
        default:
39
          break;
40
        }
41
      /* NOTREACHED */
42
      break;
43
    case 1:
44
      {
45
        /* pexp->operation must be lnot.  */
46
        unsigned long int arg = plural_eval (pexp->val.args[0], n);
47
        return ! arg;
48
      }
49
    case 2:
50
      {
51
        unsigned long int leftarg = plural_eval (pexp->val.args[0], n);
52
        if (pexp->operation == lor)
53
          return leftarg || plural_eval (pexp->val.args[1], n);
54
        else if (pexp->operation == land)
55
          return leftarg && plural_eval (pexp->val.args[1], n);
56
        else
57
          {
58
            unsigned long int rightarg = plural_eval (pexp->val.args[1], n);
59

    
60
            switch (pexp->operation)
61
              {
62
              case mult:
63
                return leftarg * rightarg;
64
              case divide:
65
#if !INTDIV0_RAISES_SIGFPE
66
                if (rightarg == 0)
67
                  raise (SIGFPE);
68
#endif
69
                return leftarg / rightarg;
70
              case module:
71
#if !INTDIV0_RAISES_SIGFPE
72
                if (rightarg == 0)
73
                  raise (SIGFPE);
74
#endif
75
                return leftarg % rightarg;
76
              case plus:
77
                return leftarg + rightarg;
78
              case minus:
79
                return leftarg - rightarg;
80
              case less_than:
81
                return leftarg < rightarg;
82
              case greater_than:
83
                return leftarg > rightarg;
84
              case less_or_equal:
85
                return leftarg <= rightarg;
86
              case greater_or_equal:
87
                return leftarg >= rightarg;
88
              case equal:
89
                return leftarg == rightarg;
90
              case not_equal:
91
                return leftarg != rightarg;
92
              default:
93
                break;
94
              }
95
          }
96
        /* NOTREACHED */
97
        break;
98
      }
99
    case 3:
100
      {
101
        /* pexp->operation must be qmop.  */
102
        unsigned long int boolarg = plural_eval (pexp->val.args[0], n);
103
        return plural_eval (pexp->val.args[boolarg ? 1 : 2], n);
104
      }
105
    }
106
  /* NOTREACHED */
107
  return 0;
108
}