use re 'debug';或use re 'debugcolor';。例如，如果你在Perl中输入以下内容：use strict;
use warnings;
use 5.010;
use re 'debug';
# using the same strings as the question's image for reference:
my $str = 'Even if I do say so myself: "RegexBuddy is awesome"';
$str =~ /(Regexp?Buddy is (awful|acceptable|awesome))/;
这是输出的结果:
Compiling REx "(Regexp?Buddy is (awful|acceptable|awesome))"
Final program:
1: OPEN1 (3)
3: EXACT <Regex> (6)
6: CURLY {0,1} (10)
8: EXACT <p> (0)
10: EXACT <Buddy is > (14)
14: OPEN2 (16)
16: EXACT <a> (18)
18: TRIEC-EXACT[cw] (29) # this is a new feature in Perl 5.10
<wful>
<cceptable>
<wesome>
29: CLOSE2 (31)
31: CLOSE1 (33)
33: END (0)
anchored "Regex" at 0 floating "Buddy is a" at 5..6 (checking floating) minlen 19
Guessing start of match in sv for REx "(Regexp?Buddy is (awful|acceptable|awesome))" against 'Even if I do say so myself: "RegexBuddy is awesome"'
Found floating substr "Buddy is a" at offset 34...
Found anchored substr "Regex" at offset 29...
Starting position does not contradict # /^/m...
Guessed: match at offset 29
Matching REx "(Regexp?Buddy is (awful|acceptable|awesome))" against 'RegexBuddy is awesome"'
29 <'lf: "'> <RegexBuddy> | 1:OPEN1(3)
29 <'lf: "'> <RegexBuddy> | 3:EXACT <Regex>(6)
34 <Regex> <Buddy is a> | 6:CURLY {0,1}(10)
EXACT <p> can match 0 times out of 1...
34 <Regex> <Buddy is a> | 10: EXACT <Buddy is >(14)
43 <y is > <'awesome"'> | 14: OPEN2(16)
43 <y is > <'awesome"'> | 16: EXACT <a>(18)
44 < is a> <'wesome"'> | 18: TRIEC-EXACT[cw](29)
44 < is a> <'wesome"'> | State: 2 Accepted: 0 Charid: 2 CP: 77 After State: 3
45 < is aw> <'esome"'> | State: 3 Accepted: 0 Charid: 7 CP: 65 After State: 10
46 < is awe> <'some"'> | State: 10 Accepted: 0 Charid: b CP: 73 After State: 11
47 < is awes> <'ome"'> | State: 11 Accepted: 0 Charid: c CP: 6f After State: 12
48 < is aweso> <'me"'> | State: 12 Accepted: 0 Charid: d CP: 6d After State: 13
49 < is awesom> <'e"'> | State: 13 Accepted: 0 Charid: 7 CP: 65 After State: 14
50 < is awesome> <'"'> | State: 14 Accepted: 1 Charid: 3 CP: 0 After State: 0
got 1 possible matches
only one match left: #3 <wesome>
50 < is awesome> <'"'> | 29: CLOSE2(31)
50 < is awesome> <'"'> | 31: CLOSE1(33)
50 < is awesome> <'"'> | 33: END(0)
Match successful!
Freeing REx: "(Regexp?Buddy is (awful|acceptable|awesome))"
这个在线工具虽然不如RegexBuddy强大，但它提供了简单易用的界面：http://www.gskinner.com/RegExr/
您可以将鼠标悬停在表达式的某些部分上，它会告诉您它正在执行什么操作。虽然很基础，但当您犯了一些错误时，它确实可以节省时间。
使用CodVerter正则表达式测试工具在线验证正则表达式模式。编辑器能够实时更新，并且可以根据需要更改标志。
作品可以本地保存或通过用户帐户中的高级存储库管理器保存到云端以供进一步编辑。当保存到云端时，您可以生成链接与任何人共享您的作品。
来自CodVerter正则表达式测试工具的IP正则表达式示例
如果您需要一个用于多个正则表达式模式的更复杂的工具，请尝试CodVerter 多个正则表达式模式扫描器
这里是有关此工具的短 教程。
（完全披露：我是CodVerter 的开发人员之一）
这可能是因为正则表达式引擎如何找到匹配项并不重要。RegexBuddy的截图让我想使用另一个正则表达式匹配器，因为不应该需要回溯。
通常，您会将正则表达式转换为非确定有限状态自动机（NFA）或确定有限状态自动机（DFA），可以处理没有回溯的正则表达式。
话虽如此，我所知道的唯一免费的创建和测试正则表达式的工具是pyreb。
