Perl语言入门-第八章-以正则表达式进行匹配-习题

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我是靠谱客的博主英俊钢笔，最近开发中收集的这篇文章主要介绍Perl语言入门-第八章-以正则表达式进行匹配-习题，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

1. 题目

2. 代码与输出

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter8,exercise-1
3 # Date:   2012-01-18
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 while(<>) {
8    chomp;
9    if( $_ =~ m|match|) {
10     say " <$`><$&><$'> ";
11   }
12 }
13 # -----------------------------------------------------------#
14 # 1. /match/ 是对 m/match/的简写
15 #    m/match/,m|match|,m<match>,m{match}这些都是等价的
16 # 2. =~可以匹配指定的变量
17 #-----------------------------------------------------------#

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter8,exercise-2
3 # Date:   2012-01-18
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 while(<>) {
8    chomp;
9    if( $_ =~ m|bw*ab|) {
10     say " <$`><$&><$'> ";
11   }
12 }
13 # -----------------------------------------------------------#
14 # 1. w等价于[A-Za-z0-9_]，即字母、数字和下划线
15 # 2. b是表示单词开始或结束位置
16 # 3. 不能匹配到Mrs._Wilma_Flintsone，因为下划线属于w，为b
17 #    匹配“非w”的位置
18 #-----------------------------------------------------------#

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter8,exercise-3
3 # Date:   2012-01-18
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 while(<>) {
8    chomp;
9    if( $_ =~ m|b(w*a)b|) {
10     say " <$`><$&><$'> ";
11     say ' $1 contains ' . " '$1' ";
12   }
13 }
14 # -----------------------------------------------------------#

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter8,exercise-4
3 # Date:   2012-01-18
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 while(<>) {
8    chomp;
9    if( $_ =~ m|b(?<word>w*a)b|) {
10     say " <$`><$&><$'> ";
11     say ' word contains ' . " '$+{word}' ";
12   }
13 }
14 # -----------------------------------------------------------#
15 # 1. 定义命名捕获 (?<命名>待捕获模式串)
16 #    使用命名捕获 $+{命名}
17 #-----------------------------------------------------------#

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter8,exercise-5
3 # Date:   2012-01-18
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 while(<>) {
8    chomp;
9    if( $_ =~ m|bw*ab(?<word>.{ 0, 5})|) {
10     say " <$`><$&><$'> ";
11     say ' $1 contains ' . " '$1' ";
12     say ' word contains ' . " '$+{word}' ";
13   }
14 }
15 # -----------------------------------------------------------#
16 # 1. 通用量词，{0,5} 0次到5次，{0,}0次或者以上
17 #-----------------------------------------------------------#

1 # -----------------------------------------------------------#
2 # Source: Learning Perl, chapter8,exercise-6
3 # Date:   2012-01-18
4 # Author: xiaodongrush
5 #-----------------------------------------------------------#
6 use 5.010;
7 while(<>) {
8    chomp;
9    if( $_ =~ m|s$|) {
10     say " |$`|$&|$'| ";
11     say " |$_| ";
12   }
13 }
14 # -----------------------------------------------------------#
15 # 如果匹配成功，那么$&将是字符串的最后一个空白，而$'是空串
16 # $`是除了最后一个空白的前面所有字符
17 #-----------------------------------------------------------#