如何通过标点符号插入空格?

Question

我有这样的字符串:hey what is up!,"what did you say?","he said 'well'"等，以及这样的正则表达式:[!%&'()$#"/\*+,-.:;<=>?@[]^_´{|}~]´。这些是我的分隔符，在显示的字符串中插入一个空格，如下所示:"hey what is up !","what did you say ?","he said ' well '"。因此，如果其中一个分隔符在另一个字符序列的前面，则添加一个空格，如果它在后面，也添加一个空格。

我怎样才能做到这一点?我不想用这些分隔符分隔。

这是我的解决方案，但我很好奇如何解决它与regex。

space = set("[!%&'()$#"/*+,-.:;<=>?@[]^_´`{|}~]")
for sent in self.sentences:
sent = list(sent)
for i, char in enumerate(sent):
# Make sure to respect length of string when indexing
if i != 0:
# insert space in front if char is punctuation
if sent[i] in space and sent[i - 1] != " ":
sent.insert(i, " ")
if i != len(sent)-1:
# insert space after if char is punctuation
if sent[i] in space and sent[i + 1] != " ":
sent.insert(i + 1, " ")

Answer 1

您可以扩展您的模式来捕获可选的空格，然后用capture group +空格替换前后(循环仅用于演示，不是必需的):

import re

strings = ["hey what is up!", "what did you say?", "he said 'well'"]
pattern = r'(s?[!%&'()$#"/\*+,-.:;<=>?@[]^_´{|}~]s?)'
for string in strings:
print(re.sub(pattern, r' 1 ', string))

输出如下:

hey what is up !
what did you say ?
he said  ' well '

Answer 2

如果没有re模块的帮助，您可以简单地这样做:

punctuation = "!%&'()$#"/\*+,-.:;<=>?@[]^_´{|}~"
mystring = "Well hello! How are you?"
mylist = list(mystring)
i = 0
for c in mystring:
if c in punctuation:
mylist.insert(i, ' ')
i += 2
else:
i += 1
print(''.join(mylist))

Answer 3

您可以创建一个遍历字符串的循环，当它找到标点符号字符时，使用slice函数将字符串切成两半，并在两者之间使用空格进行连接。例如:

for i in yourString:
if yourString[i] == '!':
newString = yourString.slice(0, i) + " " + yourString.slice(i + 1)

它只检查"!"但是你可以用标点符号

的字典来替换它