alv*_*vas 5 python yield file delimiter
我有一个这样的输入文件:
This is a text block start
This is the end
And this is another
with more than one line
and another line.
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所需的任务是按由某些特殊行分隔的部分读取文件,在本例中它是一个空行,例如 [out]:
[['This is a text block start', 'This is the end'],
['And this is another','with more than one line', 'and another line.']]
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我通过这样做得到了所需的输出:
def per_section(it):
""" Read a file and yield sections using empty line as delimiter """
section = []
for line in it:
if line.strip('\n'):
section.append(line)
else:
yield ''.join(section)
section = []
# yield any remaining lines as a section too
if section:
yield ''.join(section)
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#但如果特殊行是以eg开头的行:
# Some comments, maybe the title of the following section
This is a text block start
This is the end
# Some other comments and also the title
And this is another
with more than one line
and another line.
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我必须这样做:
def per_section(it):
""" Read a file and yield sections using empty line as delimiter """
section = []
for line in it:
if line[0] != "#":
section.append(line)
else:
yield ''.join(section)
section = []
# yield any remaining lines as a section too
if section:
yield ''.join(section)
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如果我允许per_section()有一个分隔符参数,我可以尝试这个:
def per_section(it, delimiter== '\n'):
""" Read a file and yield sections using empty line as delimiter """
section = []
for line in it:
if line.strip('\n') and delimiter == '\n':
section.append(line)
elif delimiter= '\#' and line[0] != "#":
section.append(line)
else:
yield ''.join(section)
section = []
# yield any remaining lines as a section too
if section:
yield ''.join(section)
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但是有没有办法让我不对所有可能的分隔符进行硬编码?
传递谓词怎么样?
def per_section(it, is_delimiter=lambda x: x.isspace()):
ret = []
for line in it:
if is_delimiter(line):
if ret:
yield ret # OR ''.join(ret)
ret = []
else:
ret.append(line.rstrip()) # OR ret.append(line)
if ret:
yield ret
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用法:
with open('/path/to/file.txt') as f:
sections = list(per_section(f)) # default delimiter
with open('/path/to/file.txt.txt') as f:
sections = list(per_section(f, lambda line: line.startswith('#'))) # comment
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