Naming convetion of regex,lookahead and lookbehind

Posted by user198729 on Stack Overflow See other posts from Stack Overflow or by user198729
Published on 2010-03-25T09:09:54Z Indexed on 2010/03/25 9:13 UTC
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regex

|

lookahead

|

lookbehind

Why is it counter intuitive?

/(?<!\d)\d{8}(?!\d)/,here (?<!\d) comes first,but called lookbehind,(?!\d) next,but called lookahead.All are counter intuitive.

What's the reason to name it this way?

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