Hi,

While looking at performance of a script of mine, i tested an iteration script, i found out that using a little bit more complex Regular Expressions isn't equal or faster, even though it's code is smaller (and looks nicer).

I realize this is a minor test and a fast conclusion, i hope anyone can tell me why this difference is and maybe tell me if you have experienced such differences yourself ?

Did i test this wrongly? Or would it seriously be an option to fragment a complex RE for better performance (if possible) ? 

for($i=0;$i<100000;$i++){
    if("test$i" =~ /(est|\d)/){
        # do stuff;
    }
}

is at least 20% slower (+/- 3s vs 2.3s yes, slow machine :-) then: 

for($i=0;$i<100000;$i++){
    if("test$i" =~ /est/ || "test$i" =~ /\d/){
        # do stuff;
    }
}

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In reply to RE performance by Vennis

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