Neil 在 2021年8月5日 星期四下午6:36:58 [UTC+8] 的信中寫道：
> Jach Feng <jf...@ms4.hinet.net> wrote:
> > I want to distinguish between numbers with/without a dot attached:
> >
> >>>> text = 'ch 1. is\nch 23. is\nch 4 is\nch 56 is\n'
> >>>> re.compile(r'ch \d{1,}[.]').findall(text)
> > ['ch 1.', 'ch 23.']
> >>>> re.compile(r'ch \d{1,}[^.]').findall(text)
> > ['ch 23', 'ch 4 ', 'ch 56 ']
> >
> > I can guess why the 'ch 23' appears in the second list. But how to get rid
> > of it?
> >
> > --Jach
> Does
>
> >>> re.findall(r'ch\s+\d+(?![.\d])',text)
>
> do what you want? This matches "ch", then any nonzero number of
> whitespaces, then any nonzero number of digits, provided this is not
> followed by a dot or another digit.
Yes, the result is what I want. Thank you, Neil!
The solution is more complex than I expect. Have to digest it:-)
--Jach
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