[root@stationx ch2-regular]# cat perl-grep4.pl
#!/bin/perl
# perl-grep4.pl
my $pattern = shift @ARGV;
my $regex = eval { qr/$pattern/ };
die "Check your pattern! $@" if $@;
while(<>)
??????? {
??????? if(m/$regex/)
??????????????? {
??????????????? print "$_";
??????????????? print "tt$&: ",
??????????????? substr( $_,$-[$i],$+[$i] - $-[$i] ),
??????????????? "n";
??????????????? foreach my $i ( 1 .. $#- )
??????????????????????? {
??????????????????????? print "$#-n";
??????????????????????? print "tt$$i: ",
??????????????????????? substr( $_,
??????????????????????? "n";
??????????????????????? }
??????????????? }
??????? }
[root@stationx ch2-regular]# perldoc -t perl| perl perl-grep4.pl "b(S)(S)1b"
?http://www.cpan.org/?????? the Comprehensive Perl Archive
??????????????? $&: www
??????????????? $1: w
??????????????? $2: w
???? http://www.pm.org/???????? the Perl Mongers ??????????????? $&: www ??????????????? $1: w ??????????????? $2: w [root@stationx ch2-regular]# @-和@+两个数组非常的神奇，两者保存的是matched内容的offset（偏移量）????????? 也就是说每个match内容的起始offset值放置在@-数组中，结束offset值放置在@+数组中????????? 说白了@-和@+两个数组保存的是一系列的值。????????? @-数组的第一个元素是matche内容的起始offset，@+数组的第一个元素是match内容的结尾offset????????? 随后才是$1,$2...的offset值。?????????
