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I am trying to create a regex to find the following string:

AGK-XL.

Sometimes before and after this string there are other characters that are usually harmless, except if there is the following pattern before the string:

NOT-

I need to delete/ignore those cases. This is what I have tried:

^[^N][^O][^T][^\-]AGK-XL\.(\s|\W|$)

But it only seems to match when there are exactly 4 letters in front of the string. How can I express that any other pattern besides NOT- before AGK-XL. is harmless?

Thanks for any hints. edit: I am using regex in VBA atm.

EDC
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  • Unfortunately, there is no look-behind in VBScript regex :( Use capturing groups: `NOT-AGK-XL\.(?!\w)|(AGK-XL\.(?!\w))`. – Wiktor Stribiżew Sep 24 '15 at 14:43
  • @stribizhev hmm that works, could you formulate an answer and explain it a bit maybe? – EDC Sep 24 '15 at 14:48
  • Without knowing what you do, it is a bit difficult to answer the question, but I will post an explanation of what I mean. – Wiktor Stribiżew Sep 24 '15 at 14:49
  • @stribizhev Ok thanks. I am trying to search for these strings and then delete them in a table, that is the final purpose – EDC Sep 24 '15 at 14:51

1 Answers1

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If you cannot use fancy look-behinds, you can rely on capturing mechanism when you need to match something we do not want, and match and capture what you want. See the The Best Regex Trick Ever at rexegg.com.

However, in this case, you can match and capture NOT-AGK-XL. (so that you can restore it later with $1 backreference), and only match all other occurrences of AGK-XL. that you will remove. Use alternation operator | to match both alternatives:

(NOT-AGK-XL\.(?!\w))|AGK-XL\.(?!\w)

See demo

Note I replaced (\s|\W|$) with (?!\w) that is - IMHO - a better word boundary check.

Wiktor Stribiżew
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