It's nearly always easier and quicker (in coding time if not execution time) to code that sort of test using separate regexes and boolean operators than it is a single regex. 

$_ = "hello Gags"; 
if( /hello/ and not /Ga/ ) { 
    print 'Matched' 
} 
else { 
    print 'Failed' 
};

Failed

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"Efficiency is intelligent laziness." -David Dunham
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In reply to Re: Debugging Regexes by BrowserUk
in thread Debugging Regexes by perlgags78

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