examples/functions/isnum2

   1 #
   2 #  Chet Ramey <chet.ramey@case.edu>
   3 #
   4 #  Copyright 1998 Chester Ramey
   5 #
   6 #   This program is free software; you can redistribute it and/or modify
   7 #   it under the terms of the GNU General Public License as published by
   8 #   the Free Software Foundation; either version 2, or (at your option)
   9 #   any later version.
  10 #
  11 #   TThis program is distributed in the hope that it will be useful,
  12 #   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 #   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 #   GNU General Public License for more details.
  15 #
  16 #   You should have received a copy of the GNU General Public License
  17 #   along with this program; if not, write to the Free Software Foundation,
  18 #   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19
  20 isnum2()
  21 {
  22         case "$1" in
  23         [-+] | '')      return 1;;      # empty or bare `-' or `+'
  24         [-+]*[!0-9]*)   return 1;;      # non-digit with leading sign
  25         [-+]*)          return 0;;      # OK
  26         *[!0-9]*)       return 1;;      # non-digit
  27         *)              return 0;;      # OK
  28         esac
  29 }
  30
  31 # this one handles floating point
  32 isnum3()
  33 {
  34         case "$1" in
  35         '')             return 1;;      # empty
  36         *[!0-9.+-]*)    return 1;;      # non-digit, +, -, or .
  37         *?[-+]*)        return 1;;      # sign as second or later char
  38         *.*.*)          return 1;;      # multiple decimal points
  39         *)              return 0;;      # OK
  40         esac
  41 }