最简单的方法是遍历这些行（假设您有一个行列表或一个文件，或者将字符串拆分为一个行列表），直到看到一行只是'\n'，然后检查每一行是否以'- '（使用startswithstring 方法）并将其切片，存储结果，直到找到另一个空行。例如：
# if you have a single string, split it into lines.
L = s.splitlines()
# if you (now) have a list of lines, grab an iterator so we can continue
# iteration where it left off.
it = iter(L)
# Alternatively, if you have a file, just use that directly.
it = open(....)
# Find the first empty line:
for line in it:
# Treat lines of just whitespace as empty lines too. If you don't want
# that, do 'if line == ""'.
if not line.strip():
break
# Now starts data.
for line in it:
if not line.rstrip():
# End of data.
break
if line.startswith('- '):
data.append(line[:2].rstrip())
else:
# misformed data?
raise ValueError, "misformed line %r" % (line,)
已编辑：由于您详细说明了要执行的操作，因此这里是循环的更新版本。它不再循环两次，而是收集数据直到遇到“坏”行，并在遇到块分隔符时保存或丢弃收集的行。它不需要显式迭代器，因为它不会重新开始迭代，所以你可以只传递一个行列表（或任何可迭代的）行：
def getblocks(L):
# The list of good blocks (as lists of lines.) You can also make this
# a flat list if you prefer.
data = []
# The list of good lines encountered in the current block
# (but the block may still become bad.)
block = []
# Whether the current block is bad.
bad = 1
for line in L:
# Not in a 'good' block, and encountering the block separator.
if bad and not line.rstrip():
bad = 0
block = []
continue
# In a 'good' block and encountering the block separator.
if not bad and not line.rstrip():
# Save 'good' data. Or, if you want a flat list of lines,
# use 'extend' instead of 'append' (also below.)
data.append(block)
block = []
continue
if not bad and line.startswith('- '):
# A good line in a 'good' (not 'bad' yet) block; save the line,
# minus
# '- ' prefix and trailing whitespace.
block.append(line[2:].rstrip())
continue
else:
# A 'bad' line, invalidating the current block.
bad = 1
# Don't forget to handle the last block, if it's good
# (and if you want to handle the last block.)
if not bad and block:
data.append(block)
return data
它在行动中：
>>> L = """hello
...
... - x1
... - x2
... - x3
...
... - x4
...
... - x6
... morning
... - x7
...
... world""".splitlines()
>>> print getblocks(L)
[['x1', 'x2', 'x3'], ['x4']]