How about: 
$_='JAZZxxJAZZJAZZxxJAZJAZZxxJAZZ';
print $_,$/;
s/(.*?)(JAZZ)/('a'x length $1) . $2/ge;
print

[download]
which gives: 
JAZZxxJAZZJAZZxxJAZJAZZxxJAZZ
JAZZaaJAZZJAZZaaaaaJAZZaaJAZZ

[download]

--
I'd like to be able to assign to an luser

In reply to Re: A challenging problem in perl regular expression by Albannach
in thread A challenging problem in perl regular expression by yai

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