關於perl regexp

twf_cc

這是bash 版
fang@bash ~
$ cat bin/marksix
#! /bin/bash
# marksix genertor, Usage: $0 [ [option] argument ]
#  twf_cc@yahoo.com.hk

output=""
base_array=({1..49})
length=${#base_array[@]}
argument=$1
howmany=${argument:-6}
usage="Usage:\t${0##*/} [[option] number of picks](default 6)"
message_to_user="Number of picks should not be greater than $length"
out_of_range=66
non_numberic_argument=65

  if [[ $howmany =~ [^0-9]+ ]]
    then
      echo -e "$usage" >&2 ; exit $non_numberic_argument
  elif [ $howmany -gt $length ]
    then
      echo "$message_to_user" >&2 ; exit $out_of_range
  fi

  for (( i=1 ; i<=howmany ; i++ ))
    do
      pick=${base_array[$(( RANDOM % length ))]}
      output="$output $pick"
      resize_array=($(echo ${base_array[@]} | sed "s/ $pick//")
      base_array=(${resize_array[@]})
      length=${#base_array[@]}
    done

  sort_result=$( printf '%s\n' $output | sort -n )
  echo -e ${sort_result//\n/" "}

這是Perl 版

fang@bash ~
$ cat bin/marksix.pl
#! /usr/bin/perl
# marksix generator, perl version
# twf_cc@yahoo.com.hk

@num=qw(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
        23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41
        42 43 44 45 46 47 48 49) ;
$length=@num ;
$output="" ;
$howmany=$ARGV[0] ;
$i=1 ;
  
  die "Number of picks should not be greater than $length\n" if ($howmany > $length) ;
  die "Usage:\t$0 [[option]number of picks](default 6)\n" if ($howmany =~ /\D+/) ;
  $howmany = 6 if (@ARGV == 0) ;

  while ($i <= $howmany){
    srand ;
    $random=int(rand() * $length * $i) % $length ;
    $pick=$num[$random] ;
    $output="$output $pick" ;
    splice (@num, $random, 1) ;
    $length=@num ;
    $i++ ;
  }
  @out=split(" ", $output) ;
  @sorted=sort {$a <=> $b} @out ;
  print "@sorted\n"

這是 ash + GNU grep 版

fang@bash ~
$ cat bin/lotto
#! /bin/ash
# Usage: $0 [ [option] argument ]  
#  twf_cc@yahoo.com.hk
# set -x

output=
draw="1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 \
      21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 \
      38 39 40 41 42 43 44 45 46 47 48 49"
length=`echo $draw | tr ' ' '\n' | wc -l`
argument=$1
howmany=${argument:-6}
usage="Usage:  `basename $0` [[option] number of picks](default 6)"
message="Number of picks should not be greater than $length"
non_numberic=65
out_of_range=66
step=1

  if echo "$howmany" | grep '[^0-9][^0-9]*' > /dev/null 2>&1
    then
      echo "$usage" 1>&2
      exit $non_numberic
  fi
  if [ $howmany -gt $length ]
    then
      echo "$message" 1>&2
      exit $out_of_range
  fi
  
  while [ $step -le $howmany ]
    do
      random=`awk -v remainder=$length  -v base=$$  -v step=$step '
              BEGIN{
                     srand()
                     print  int(rand() * base * step )  % remainder + 1
              }'`
      pick=`echo $draw | tr ' ' '\n' | head -n"$random" | tail -n1`
      output="$output $pick"
      resize_draw=`echo $draw | sed -e "s/ $pick//"`
      draw="$resize_draw"
      length=`echo $draw | tr ' ' '\n' | wc -l`
      step=`expr $step + 1`
    done
   
    echo $output | tr ' ' '\n' | sort -n | tr '\n' ' '
    echo ""

screen shot
fang@bash ~
$ uname -a
CYGWIN_NT-5.1 bash 1.5.25(0.156/4/2) 2007-12-14 19:21 i686 Cygwin

fang@bash ~
$ marksix 89
Number of picks should not be greater than 49

fang@bash ~
$ marksix 89j
Usage:  marksix [[option] number of picks](default 6)

fang@bash ~
$ marksix 49j
Usage:  marksix [[option] number of picks](default 6)

fang@bash ~
$ marksix.pl 49j
Usage:  /home/fang/bin/marksix.pl [[option]number of picks](default 6)

fang@bash ~
$ marksix.pl 89j
Number of picks should not be greater than 49

fang@bash ~
$ marksix.pl 89
Number of picks should not be greater than 49

fang@bash ~
$ lotto 49j
Usage:  lotto [[option] number of picks](default 6)

fang@bash ~
$ lotto 89j
Usage:  lotto [[option] number of picks](default 6)

fang@bash ~
$ lotto 89
Number of picks should not be greater than 49

fang@bash ~
$

fang@bash ~
$ bash --version | head -n2
GNU bash, version 3.2.33(1-release (i686-pc-cygwin)
Copyright (C) 2007 Free Software Foundation, Inc.

fang@bash ~
$ perl --version | head -n2

This is perl, v5.8.8 built for cygwin-thread-multi-64int

fang@bash ~
$ grep --version | head -n2
grep (GNU grep) 2.5.1

Perl 不同於其他程式的 regexp engine?  /\D+/ 該等如 /[^0-9]+/  or /[^0-9][^0-9]*/ 的呀?

churchmice

原帖由 twf_cc 于 2008-3-3 23:18 发表
這是bash 版
fang@bash ~
$ cat bin/marksix
#! /bin/bash
# marksix genertor, Usage: $0 [ [option] argument ]
#  twf_cc@yahoo.com.hk

output=""
base_array=({1..49})
length=${#base_array[@]} ...

因为你的$ARGV[0]是49j
$ARGV =~ /\D+/
这个是匹配的
除非你在regex前面显示的加上anchor
try

1. 
   
2. $ARGV[0] =~ /^\D+/;
   

复制代码

ps:最好说一下程序是用来干什么的
看代码推断实在头痛