How to Match Regex Instances Outside of Quotes, Including Escaped Quotes?

Matching Regex Instances Outside of Quotes

While it is generally challenging to match regex instances that are not enclosed within quotes, there is indeed a possible solution.

To achieve this, we consider the following property: a word is outside quotes if there are an even number of quotes after it. This property can be captured using a look-ahead assertion:

\+(?=([^"]*"[^"]*")*[^"]*$)

However, this assertion doesn't account for escaped quotes. To handle them, we modify the pattern to consider both characters and backslashes while ignoring backslash-escaped characters:

\+(?=([^"\]*(\.|"([^"\]*\.)*[^"\]*"))*[^"]*$)

This complex pattern allows us to identify all instances of the ' ' character that are not within quotes, effectively excluding both double-quoted and escaped sequences. While the pattern may appear somewhat cryptic, it enables us to perform precise matching outside of quotes.

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