Hi everyone, I am running into a strange regex issue.... I have a document where I am doing a replace... as an example I want to replace "DEXX" with "DEXX/AREX" and then with the next substitution replace... "AREX" with "AREX/CUBE"

DEXX and AREX are stored in a hash like so.... "DEXX" => "AREX", "AREX" => "CUBE"

The regex I have is this.....

foreach (keys %hashstore){
    $doc=~s!\b($_)\b!$1/$hashstore{$_}!ig;
}

[download]

What's happening is that "DEXX" is being replaced with "DEXX/AREX" ok but when "DEXX/AREX" is encountered the regex is replacing "DEXX/AREX" with "DEXX/AREX/CUBE" when it should only be replacing "AREX" when it finds it as a standalone word not as part of another combination like "DEXX/AREX"

I thought that a negative lookback might work . i.e.....

foreach (keys %hashstore){
    $doc=~s#(?<!/)\b($_)\b#$1/$hashstore{$_}#ig;
}

[download]

No luck though

It seems to detect "/" as a word boundary. Has anyone encountered this or know of a fix around it? Many thanks!

In reply to Getting around "/" as a word boundary by sherab

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