I'm using Java regular expressions to match and capture a string such as:
0::10000
A solution would be:
(0::\d{1,8})
However, the match would succeed for the input
10::10000
As well, which is wrong. Therefore, I now have:
\[^\d\](0::\d{1,8})
Which means it must lead with any character except a number, but that means there needs to be some character before the first zero. What I really want (and what I need help with) is to say "lead with a non-number or nothing at all."
In conclusion the final solution regular expression should match the following:
0::10000
kjkj0::10000
And should not match the following:
10::10000
This site may be of use if someone wants to help.
You need a negative lookbehind:
(?<!\d)(0::\d{1,8})
It means "match 0::\d{1,8} not preceded by \d".