我argparse在Python 2.7中用于解析输入选项.我的一个选择是多选.我想在其帮助文本中列出一个列表,例如
from argparse import ArgumentParser
parser = ArgumentParser(description='test')
parser.add_argument('-g', choices=['a', 'b', 'g', 'd', 'e'], default='a',
help="Some option, where\n"
" a = alpha\n"
" b = beta\n"
" g = gamma\n"
" d = delta\n"
" e = epsilon")
parser.parse_args()
但是,argparse删除所有换行符和连续空格.结果看起来像
~/Downloads:52$ python2.7 x.py -h
usage: x.py [-h] [-g {a,b,g,d,e}]
test
optional arguments:
-h, --help show this help message and exit
-g {a,b,g,d,e} Some option, where a = alpha b = beta g = gamma d = delta e
= epsilon
如何在帮助文本中插入换行符？
Mic*_*ski 363
尝试使用RawTextHelpFormatter:
from argparse import RawTextHelpFormatter
parser = ArgumentParser(description='test', formatter_class=RawTextHelpFormatter)
Ant*_*hon 72
如果您只想覆盖一个选项,则不应使用RawTextHelpFormatter.而是继承子类HelpFormatter并为应该处理"raw"的选项提供一个特殊的介绍(我使用"R|rest of help"):
import argparse
class SmartFormatter(argparse.HelpFormatter):
def _split_lines(self, text, width):
if text.startswith('R|'):
return text[2:].splitlines()
# this is the RawTextHelpFormatter._split_lines
return argparse.HelpFormatter._split_lines(self, text, width)
并使用它:
from argparse import ArgumentParser
parser = ArgumentParser(description='test', formatter_class=SmartFormatter)
parser.add_argument('-g', choices=['a', 'b', 'g', 'd', 'e'], default='a',
help="R|Some option, where\n"
" a = alpha\n"
" b = beta\n"
" g = gamma\n"
" d = delta\n"
" e = epsilon")
parser.parse_args()
任何其他调用.add_argument()帮助不会开始的地方R|都将正常包装.
这是我对argparse的改进的一部分.完整的SmartFormatter还支持将默认值添加到所有选项以及实用程序描述的原始输入.完整版本有自己的_split_lines方法,因此保留对例如版本字符串的任何格式:
parser.add_argument('--version', '-v', action="version",
version="version...\n 42!")
Wan*_*'an 30
另一种简单的方法是包含textwrap.
例如,
import argparse, textwrap
parser = argparse.ArgumentParser(description='some information',
usage='use "python %(prog)s --help" for more information',
formatter_class=argparse.RawTextHelpFormatter)
parser.add_argument('--argument', default=somedefault, type=sometype,
help= textwrap.dedent('''\
First line
Second line
More lines ... '''))
这样,我们可以避免每条输出线前面的长空间.
usage: use "python your_python_program.py --help" for more information
Prepare input file
optional arguments:
-h, --help show this help message and exit
--argument ARGUMENT
First line
Second line
More lines ...
Ber*_*ner 12
我承认我发现这是一次非常令人沮丧的经历，就像许多其他人一样，考虑到我看到发布的解决方案的数量以及我在网络上看到这个问题的次数。但我发现这些解决方案中的大多数对我来说太复杂了，我想分享我所拥有的最简单的解决方案。
这是演示的脚本：
#!/usr/bin/python3
import textwrap
from argparse import ArgumentParser, HelpFormatter
class RawFormatter(HelpFormatter):
def _fill_text(self, text, width, indent):
return "\n".join([textwrap.fill(line, width) for line in textwrap.indent(textwrap.dedent(text), indent).splitlines()])
program_descripton = f'''
FunkyTool v1.0
Created by the Funky Guy on January 1 2020
Copyright 2020. All rights reserved.
Licensed under The Hippocratic License 2.1
https://firstdonoharm.dev/
Distributed on an "AS IS" basis without warranties
or conditions of any kind, either express or implied.
USAGE:
'''
parser = ArgumentParser(description=program_descripton, formatter_class=RawFormatter)
args = parser.parse_args()
这是它的样子test.py：
$ ./test.py --help
usage: test.py [-h]
FunkyTool v1.0
Created by the Funky Guy on January 1 2020
Copyright 2020. All rights reserved.
Licensed under The Hippocratic License 2.1
https://firstdonoharm.dev/
Distributed on an "AS IS" basis without warranties
or conditions of any kind, either express or implied.
USAGE:
optional arguments:
-h, --help show this help message and exit
因此，原始描述中的所有基本格式都被整齐地保留下来，唉，我们不得不使用自定义格式化程序，但它是一个单行代码。可以更清晰地写成：
$ ./test.py --help
usage: test.py [-h]
FunkyTool v1.0
Created by the Funky Guy on January 1 2020
Copyright 2020. All rights reserved.
Licensed under The Hippocratic License 2.1
https://firstdonoharm.dev/
Distributed on an "AS IS" basis without warranties
or conditions of any kind, either express or implied.
USAGE:
optional arguments:
-h, --help show this help message and exit
但我自己更喜欢单行。
fla*_*z14 11
我遇到过类似的问题(Python 2.7.6).我试图将描述部分分成几行,使用RawTextHelpFormatter:
parser = ArgumentParser(description="""First paragraph
Second paragraph
Third paragraph""",
usage='%(prog)s [OPTIONS]',
formatter_class=RawTextHelpFormatter)
options = parser.parse_args()
得到了:
usage: play-with-argparse.py [OPTIONS]
First paragraph
Second paragraph
Third paragraph
optional arguments:
-h, --help show this help message and exit
所以RawTextHelpFormatter不是解决方案.因为它打印源代码中显示的描述,保留所有空格字符(我想在我的源代码中保留额外的选项卡以便于阅读,但我不想全部打印它们.而且原始格式化程序在它是时不会换行太长,例如超过80个字符).
由于@Anton谁启发了正确的方向之上.但是该解决方案需要稍微修改才能格式化描述部分.
无论如何,需要自定义格式化程序.我扩展了现有的HelpFormatter类和overrode _fill_text方法,如下所示:
import textwrap as _textwrap
class MultilineFormatter(argparse.HelpFormatter):
def _fill_text(self, text, width, indent):
text = self._whitespace_matcher.sub(' ', text).strip()
paragraphs = text.split('|n ')
multiline_text = ''
for paragraph in paragraphs:
formatted_paragraph = _textwrap.fill(paragraph, width, initial_indent=indent, subsequent_indent=indent) + '\n\n'
multiline_text = multiline_text + formatted_paragraph
return multiline_text
与来自argparse模块的原始源代码比较:
def _fill_text(self, text, width, indent):
text = self._whitespace_matcher.sub(' ', text).strip()
return _textwrap.fill(text, width, initial_indent=indent,
subsequent_indent=indent)
在原始代码中,整个描述被包装.在上面的自定义格式化程序中,整个文本被分成几个块,每个块都是独立格式化的.
所以借助自定义格式化程序:
parser = ArgumentParser(description= """First paragraph
|n
Second paragraph
|n
Third paragraph""",
usage='%(prog)s [OPTIONS]',
formatter_class=MultilineFormatter)
options = parser.parse_args()
输出是:
usage: play-with-argparse.py [OPTIONS] First paragraph Second paragraph Third paragraph optional arguments: -h, --help show this help message and exit
小智 10
RawTextHelpFormatter使用和处理缩进来获取新行的另一种简单方法是
import argparse
parser = argparse.ArgumentParser(
description='test', formatter_class=argparse.RawTextHelpFormatter)
parser.add_argument('-g', choices=['a', 'b', 'g', 'd', 'e'], default='a',
help=('Some option, where\n'
' a = alpha\n'
' b = beta\n'
' g = gamma\n'
' d = delta\n'
' e = epsilon'))
parser.parse_args()
输出是
$ python2 x.py -h
usage: x.py [-h] [-g {a,b,g,d,e}]
test
optional arguments:
-h, --help show this help message and exit
-g {a,b,g,d,e} Some option, where
a = alpha
b = beta
g = gamma
d = delta
e = epsilon