because it's a syntax error :-)

See tr, s, and perlre for how to write tr operations, and proper regular expressions.

I can only guess at what you're trying to do, but did you mean the following instead? 

$value =~ s{\Q[/url][\E}
           {[/url] [}g;

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In reply to Re: How to use tr/// by rhesa
in thread How to use tr/// by ApolloOne

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