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I need a regex to search for the string SQLHELPER that ignores commented code (single line comment or multi line comments). I am searching in visual studio.

wazz
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sagar
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  • It is too hard to determine if a string is within multi line comments using regex – Jacob Boertjes Jul 12 '18 at 18:36
  • Possible duplicate of [Exclude comments when searching in Visual Studio](https://stackoverflow.com/questions/11314366/exclude-comments-when-searching-in-visual-studio) – Jacob Boertjes Jul 12 '18 at 18:46
  • @JacobBoertjes : Yes , this might be a duplicate , but original post does not answer , how to exclude multi line comments , I had checked that post already.But I am looking for a single REGEX which can ignore both Single and multi line comments – sagar Jul 12 '18 at 18:51
  • After reading to comments on the other question, I would conclude that it is not possible to exclude multi line comments. Unfortunately the answers provided there are the best you are going to get. – Jacob Boertjes Jul 12 '18 at 18:52
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    Try [`(? – Wiktor Stribiżew Jul 12 '18 at 19:45
  • Will Visual Studio accept a lookbehind of non-fixed width though? – Jacob Boertjes Jul 12 '18 at 19:52
  • @WiktorStribiżew , THANKS Wiktor , it solved my problem , now it seaches in single and multi line comments also – sagar Jul 17 '18 at 10:16
  • So, shall I post an answer? You wanted to match outside of them, right? – Wiktor Stribiżew Jul 17 '18 at 10:18
  • @WiktorStribiżew yes , post it as answer , it solves my problem , i tried searching for word SQLHELPER in all .CS file in VS , and it did not list commented out code ( single or multi ) , which was my requirment, thanks again – sagar Jul 17 '18 at 10:20

1 Answers1

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You may use

(?<!^[\p{Zs}\t]*//.*)(?<!/\*(?:(?!\*/)[\s\S\r])*?)\bSQLHELPER\b

See the regex demo.

Details

  • (?<!^[\p{Zs}\t]*//.*) - a negative lookbehind that fails the match if, immediately to the left of the current location, the following pattern does not match:
    • ^ - start of line
    • [\p{Zs}\t]* - any 0+ horizontal whitespaces
    • // - a // substring
    • .* - any 0+ chars other than line break chars
  • (?<!/\*(?:(?!\*/)[\s\S\r])*?) - - a negative lookbehind that fails the match if, immediately to the left of the current location, the following pattern does not match:
    • /\* - a /* substring
    • (?:(?!\*/)[\s\S\r])*? - (tempered greedy token) any char (matched with [\s\S\r]), 0 or more repetitions but as few as possible (due to *?) that does not start a */ substring (due to the (?!\*/) negative lookahead)
  • \bSQLHELPER\b - a whole word SQLHelper (\b are word boundaries).

enter image description here

Wiktor Stribiżew
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  • If I use this in java I get :> java.util.regex.PatternSyntaxException: Look-behind group does not have an obvious maximum length near index 48 – Fergal Fitz Sep 21 '20 at 16:30
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    @FergalFitz Of course, it is a JS ECMAScript 2018+ compliant regex. You can only use it in .NET, JS or Python PyPi regex. – Wiktor Stribiżew Sep 21 '20 at 16:39