如何根据条件从字符串的开头删除文本？

Question

suppose i have the following text:

'Reuters - Life is beautiful.'
'agency.com - China\'s currency remains pegged to the dollar and the US currency\'s sharp falls in recent months have therefore made - Chinese export prices highly competitive.'
'AP - The number of days that beaches closed or posted warnings because of pollution rose sharply in 2003 due to more rainfall, increased monitoring and tougher -standards, an environmental group said on Thursday.'
'CNN - Warming water temperatures - in the central equatorial Pacific last month may indicate the start of a new El Nino.'

I want to remove all text only at the beginning of the text that's before a "-" and only if the "-" is followed by a whitespace.

I would like something like:

if line.startswith(code_to_match_my_condition):
      strip_matched_text_from_line

So the results would be:

'Life is beautiful.'
'China\'s currency remains pegged to the dollar and the US currency\'s sharp falls in recent months have therefore made - Chinese export prices highly competitive.'
'The number of days that beaches closed or posted warnings because of pollution rose sharply in 2003 due to more rainfall, increased monitoring and tougher -standards, an environmental group said on Thursday.'
'Warming water temperatures - in the central equatorial Pacific last month may indicate the start of a new El Nino.'

I actually don't know how to code this. I would appreciate any help on this.

Thank you very much in advance

Answer 1

You might want to use a regular expression, such as

^[^-]+-\s+

and replace this with an empty string, see a demo on regex101.com .

---

In Python this could be:

import re

strings = ['Reuters - Life is beautiful.',
           'agency.com - China\'s currency remains pegged to the dollar and the US currency\'s sharp falls in recent months have therefore made - Chinese export prices highly competitive.',
           'AP - The number of days that beaches closed or posted warnings because of pollution rose sharply in 2003 due to more rainfall, increased monitoring and tougher -standards, an environmental group said on Thursday.',
           'CNN - Warming water temperatures - in the central equatorial Pacific last month may indicate the start of a new El Nino.']

rx = re.compile(r'^[^-]+-\s+')

strings = list(map(lambda string: rx.sub("", string), strings))
print(strings)

And yields

['Life is beautiful.', "China's currency remains pegged to the dollar and the US currency's sharp falls in recent months have therefore made - Chinese export prices highly competitive.", 'The number of days that beaches closed or posted warnings because of pollution rose sharply in 2003 due to more rainfall, increased monitoring and tougher -standards, an environmental group said on Thursday.', 'Warming water temperatures - in the central equatorial Pacific last month may indicate the start of a new El Nino.']

Answer 2

Simple, readable code to search and remove the block:

if " - " in line:
    index = line.find(" - ")
    line = line[index+3:]