在Python中通过正则表达式对字符串进行分区

Question

我需要在字边界（空格）上将字符串拆分为数组，同时保留空格。

例如：

'this is  a\nsentence'

将成为

['this', ' ', 'is', '  ', 'a' '\n', 'sentence']

我了解 str.partition 和 re.split，但是它们都没有完全达到我想要的效果，并且没有 re.partition。

我应该如何在Python中以合理的效率对空格进行字符串分区？

Answer 1

试试这个：

s = "this is  a\nsentence"
re.split(r'(\W+)', s) # Notice parentheses and a plus sign.

结果将是：

['this', ' ', 'is', '  ', 'a', '\n', 'sentence']

Answer 2

re 中的空白符号是 '\s' 而不是 '\W'

比较：

import re


s = "With a sign # written @ the beginning , that's  a\nsentence,"\
    '\nno more an instruction!,\tyou know ?? "Cases" & and surprises:'\
    "that will 'lways unknown **before**, in 81% of time$"


a = re.split('(\W+)', s)
print a
print len(a)
print

b = re.split('(\s+)', s)
print b
print len(b)

产生

['With', ' ', 'a', ' ', 'sign', ' # ', 'written', ' @ ', 'the', ' ', 'beginning', ' , ', 'that', "'", 's', '  ', 'a', '\n', 'sentence', ',\n', 'no', ' ', 'more', ' ', 'an', ' ', 'instruction', '!,\t', 'you', ' ', 'know', ' ?? "', 'Cases', '" & ', 'and', ' ', 'surprises', ':', 'that', ' ', 'will', " '", 'lways', ' ', 'unknown', ' **', 'before', '**, ', 'in', ' ', '81', '% ', 'of', ' ', 'time', '
, '']
57

['With', ' ', 'a', ' ', 'sign', ' ', '#', ' ', 'written', ' ', '@', ' ', 'the', ' ', 'beginning', ' ', ',', ' ', "that's", '  ', 'a', '\n', 'sentence,', '\n', 'no', ' ', 'more', ' ', 'an', ' ', 'instruction!,', '\t', 'you', ' ', 'know', ' ', '??', ' ', '"Cases"', ' ', '&', ' ', 'and', ' ', 'surprises:that', ' ', 'will', ' ', "'lways", ' ', 'unknown', ' ', '**before**,', ' ', 'in', ' ', '81%', ' ', 'of', ' ', 'time
]
61

Answer 3

试试这个：

re.split('(\W+)','this is  a\nsentence')