/* $NetBSD: eval-plural.h,v 1.1.1.1 2016/01/10 21:36:17 christos Exp $ */ /* Plural expression evaluation. Copyright (C) 2000, 2001 Free Software Foundation, Inc. This program 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. This program 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 this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifndef STATIC #define STATIC static #endif /* Evaluate the plural expression and return an index value. */ STATIC unsigned long int plural_eval PARAMS ((struct expression *pexp, unsigned long int n)) internal_function; STATIC unsigned long int internal_function plural_eval (pexp, n) struct expression *pexp; unsigned long int n; { switch (pexp->nargs) { case 0: switch (pexp->operation) { case var: return n; case num: return pexp->val.num; default: break; } /* NOTREACHED */ break; case 1: { /* pexp->operation must be lnot. */ unsigned long int arg = plural_eval (pexp->val.args[0], n); return ! arg; } case 2: { unsigned long int leftarg = plural_eval (pexp->val.args[0], n); if (pexp->operation == lor) return leftarg || plural_eval (pexp->val.args[1], n); else if (pexp->operation == land) return leftarg && plural_eval (pexp->val.args[1], n); else { unsigned long int rightarg = plural_eval (pexp->val.args[1], n); switch (pexp->operation) { case mult: return leftarg * rightarg; case divide: return leftarg / rightarg; case module: return leftarg % rightarg; case plus: return leftarg + rightarg; case minus: return leftarg - rightarg; case less_than: return leftarg < rightarg; case greater_than: return leftarg > rightarg; case less_or_equal: return leftarg <= rightarg; case greater_or_equal: return leftarg >= rightarg; case equal: return leftarg == rightarg; case not_equal: return leftarg != rightarg; default: break; } } /* NOTREACHED */ break; } case 3: { /* pexp->operation must be qmop. */ unsigned long int boolarg = plural_eval (pexp->val.args[0], n); return plural_eval (pexp->val.args[boolarg ? 1 : 2], n); } } /* NOTREACHED */ return 0; }