如何解析此列表中的元素？

Question

我有一个要解析的列表（但我正在寻找一种通用的方法来解析这样的列表）：

dev-libs/icu-63.1-r1 alpha amd64 arm arm64 ia64 ppc ppc64 x86 hppa s390 dev-libs/icu-layoutex-63.1 alpha amd64 ia64 ppc ppc64 x86 hppa sparc dev-lang/perl-5.28-r1 s390 virtual/ruby_gems-0.3_pre24 amd64 x86

有时会出现这种情况，因为它会尝试解析架构列表，比如从alpha开始直到行尾，但我真的想忽略包版本之后的所有内容，而在版本之后保留空间存在的可能性。你知道吗

我的代码如下：（打印只是为了调试）

for line in args.list:
    print(line)
    package_category = re.search(r'((?<==)\w+-\w+|\w+-\w+|\w+)', line).group(0)
    print(package_category)
    package_name = re.search(r'(?<=/)[a-z]+.[a-z]+', line).group(0)
    print(package_name)
    package_version = re.search(r'(?<=-)\d+.\d-*\w*\s?', line).group(0)

我希望这样做：

package\u category变量应包含如下类别：

dev-libs dev-lang virtual

包名称应包含包名称，如：

icu icu-layoutex perl ruby_gems

软件包版本：

63.1-r1 63.1 0.3_pre24

剩下的应该忽略不计

目前，我突然以某种方式点击了archistructures列表，结果是：

dev-libs/icu-63.1-r1 dev-libs icu alpha alpha Traceback (most recent call last): File "./repomator.py", line 47, in <module> package_name = re.search(r'(?<=/)[a-z]+.[a-z]+', line).group(0) AttributeError: 'NoneType' object has no attribute 'group'

Answer 1

这就是你想要的：

(?P<category>\w+(?:-\w+)?)/(?P<name>[a-z]+(?:[-_][a-z]+)?)-(?P<version>\S+)

Demo

说明：

(?<category>            # named group category
  \w+                   # 1 or more word character
  (?:-\w+)?             # optional, a dash then 1 or more word character
)                       # end group
/                       # a slash
(?<name>                # named group name
  [a-z]+                # 1 or more alpha
  (?:[-_][a-z]+)?       # optional, dash or underscore and 1 or more alpha
)                       # end group
-                       # a dash
(?<version>             # named group version
  \S+                   # 1 or more non space character
)                       # end group

代码：

import re

list = [
'dev-libs/icu-63.1-r1 alpha amd64 arm arm64 ia64 ppc ppc64 x86 hppa s390 ',
'dev-libs/icu-layoutex-63.1 alpha amd64 ia64 ppc ppc64 x86 hppa sparc',
'dev-lang/perl-5.28-r1 s390',
'virtual/ruby_gems-0.3_pre24 amd64 x86'
]
for line in list:
    res = re.search(r'(?P<category>\w+(?:-\w+)?)/(?P<name>[a-z]+(?:[-_][a-z]+)?)-(?P<version>\S+)', line)
    print "cat: ",res.group('category'),"\t  name: ",res.group('name'), "\t\tversion: ",res.group('version')

输出：

cat:  dev-libs    name:  icu        version:  63.1-r1
cat:  dev-libs    name:  icu-layoutex       version:  63.1
cat:  dev-lang    name:  perl       version:  5.28-r1
cat:  virtual     name:  ruby_gems      version:  0.3_pre24