Like this? 

$s = 'a b & &   *   * * * a * * * *& && & xy a';;

$s =~ s[(?<=\W)\s+(?=\W)][]g;;

 print $s;;
a b &&**** a ****&&&& xy a

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In reply to Re: string substitution by BrowserUk
in thread string substitution by Gosh

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