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regexanchormatchingword-boundary

Regex for matching of anchor negation and string

I'm trying add a space before a particular string (Token for example) by replacing a regex with another: somethingToken should become something Token but something Token should stay something Token_ and not something Token (with 2 spaces)

I'm having trouble finding a regex that would match a non-space character and then the Token but without including the non-space character in the match (otherwise it would get replaced as well). A (failed) attempt was to try to negate a \b anchor (which should match the beginning of a word), but I don't know if I can negate an anchor. Any help on this is appreciated. Thanks.

Solution

  • I have just found the answer to this, perhaps it will be useful for someone else: 

    \BToken

    which represents a negated word boundary, so essentially matching wherever the standard word boundary (\b) does not match. For my example, it does indeed match somethingToken but not something Token which is left as is.