OK, thanks. Considering switching to greedy instead of non-greedy results in the regex 
    $string =~ /
        (                                    
            HIT                                
            (?=                                
                [^<]*                        
                (?!                            
                    <a[^>]*>                
                )                
                .*?<\/a>                    
            )                                
            .*?<\/a>                        
        )
    /x;

[download]
but still gives the same results. If the $string 
'<a href="#1">--HIT<a name="MUST NOT MATCH">--</a> <a href="#2">2</a>'

[download]
does properly not match and 
'<a href="#1">--HIT-<a name="MUST NOT MATCH">--</a> <a href="#2">2</a>
+'

[download]
does "falsely" match I don't understand why the problem lies in the fact that a negative lookahead does not backtrack.

In reply to Re: Re: Re: Re: negative Lookahead by eddmund
in thread negative Lookahead or by eddmund

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