Regex 字符串匹配与提取

我有一个类似“ab.cde.fg.hi”的字符串，我想把它分成两个字符串

“ab.cde.fg”

“嗨”

如何做到这一点？我写了一些代码，可以得到第二个字符串，但是我如何检索剩余的呢

$mystring = "ab.cde.fg";
$mystring =~ m/.*(\..+)/;
print "$1\n";

您还可以使用

拆分

：

my ($first, $second) = split /(?=\.[^.]+$)/, $string;

---

你确定你不是在找

($name,$path,$suffix) = File::Basename::fileparse($fullname,@suffixlist);

更新：我读错了。“.”应该包含在第二部分中，但不在上面。以上内容应为：

my @parts = /(.*)(\..*)/s;

my @parts = split /(?=\.(?!.*\.))/s;

my @parts = split /(?=\.[^.]*\z)/s;

---

为了推广我的想法，使用rindex

   1) "ab.cde.fg" 
   2) ".hi"

从

“ab.cde.fg.hi”

，我编写了这个脚本以简化实验：

  use strict;
  use diagnostics;
  use warnings;
  use English;

  my @tests = (
      [ 'ab.cde.fg.hi', 'ab.cde.fg|.hi' ]
    , [ 'abxcdexfg.hi', 'abxcdexfg|.hi' ]
  );
  for my $test (@tests) {
    my $src = $test->[0];
    my $exp = $test->[1];
    printf "-----|%s| ==> |%s|-----\n", $src, $exp;
    for my $op (
        [ 'ikegami 1' , sub { shift =~ /(.*)\.(.*)/s; } ]
      , [ 'ikegami 2' , sub { split( /\.(?!.*\.\z)/s, shift) } ]
      , [ 'rindex'    , sub { my $p = rindex( $_[0], '.' );
                              (   substr($_[0], 0, $p)
                                , substr($_[0], $p)
                              ); }
        ]
    ) {
      my ($head, $tail) = $op->[1]( $src );
      my $res = join '|', ($head, $tail);
      my $ok  = $exp eq $res ? 'ok' : "fail: $exp expected.";
      printf "%12s: %-20s => %-20s : %s\n", $op->[0], $src, $res, $ok;
    }
  }

输出：

-----|ab.cde.fg.hi| ==> |ab.cde.fg|.hi|-----
   ikegami 1: ab.cde.fg.hi         => ab.cde.fg|hi         : fail: ab.cde.fg|.hi expected.
   ikegami 2: ab.cde.fg.hi         => ab|cde               : fail: ab.cde.fg|.hi expected.
      rindex: ab.cde.fg.hi         => ab.cde.fg|.hi        : ok
-----|abxcdexfg.hi| ==> |abxcdexfg|.hi|-----
   ikegami 1: abxcdexfg.hi         => abxcdexfg|hi         : fail: abxcdexfg|.hi expected.
   ikegami 2: abxcdexfg.hi         => abxcdexfg|hi         : fail: abxcdexfg|.hi expected.
      rindex: abxcdexfg.hi         => abxcdexfg|.hi        : ok

---

应该提到的是，最后两个拆分了

$\ucode>string@eugeney，所有6个变量都在
$\uuu
上运行，尽管所有6个变量都可以轻松调整以在不同的变量上工作。
  use strict;
  use diagnostics;
  use warnings;
  use English;

  my @tests = (
      [ 'ab.cde.fg.hi', 'ab.cde.fg|.hi' ]
    , [ 'abxcdexfg.hi', 'abxcdexfg|.hi' ]
  );
  for my $test (@tests) {
    my $src = $test->[0];
    my $exp = $test->[1];
    printf "-----|%s| ==> |%s|-----\n", $src, $exp;
    for my $op (
        [ 'ikegami 1' , sub { shift =~ /(.*)\.(.*)/s; } ]
      , [ 'ikegami 2' , sub { split( /\.(?!.*\.\z)/s, shift) } ]
      , [ 'rindex'    , sub { my $p = rindex( $_[0], '.' );
                              (   substr($_[0], 0, $p)
                                , substr($_[0], $p)
                              ); }
        ]
    ) {
      my ($head, $tail) = $op->[1]( $src );
      my $res = join '|', ($head, $tail);
      my $ok  = $exp eq $res ? 'ok' : "fail: $exp expected.";
      printf "%12s: %-20s => %-20s : %s\n", $op->[0], $src, $res, $ok;
    }
  }

-----|ab.cde.fg.hi| ==> |ab.cde.fg|.hi|-----
   ikegami 1: ab.cde.fg.hi         => ab.cde.fg|hi         : fail: ab.cde.fg|.hi expected.
   ikegami 2: ab.cde.fg.hi         => ab|cde               : fail: ab.cde.fg|.hi expected.
      rindex: ab.cde.fg.hi         => ab.cde.fg|.hi        : ok
-----|abxcdexfg.hi| ==> |abxcdexfg|.hi|-----
   ikegami 1: abxcdexfg.hi         => abxcdexfg|hi         : fail: abxcdexfg|.hi expected.
   ikegami 2: abxcdexfg.hi         => abxcdexfg|hi         : fail: abxcdexfg|.hi expected.
      rindex: abxcdexfg.hi         => abxcdexfg|.hi        : ok