Re: Regex advice

John W. Krahn wrote:
> Steve Bertrand wrote:
>> Hi everybody,
> 
> Hello,
> 
>> I am far from a regex guru, so I know that I can get advice on how to 
>> learn to improve my regex knowledge so I can better my currently working 
>> code to protect against failure in the future. I would appreciate some 
>> criticism, with explanations as to the changes if possible.
>>
>> I've made it as brief as possible, with hopefully enough context (sorry 
>> if it wraps):
>>
>>
>> while (<LOG>) {
>>
>> if (/.*simscan~\[\d+\]~([\w|\s]+).*?~(\d+\.\d+)s~.*?~(.*?)~(.*?)~(.*)/) {
> 
> The .* pattern at the beginning is useless as it causes unnecessary 
> back-tracking, just remove it.

That depends on the target data. If the rest of the regular expression matches
the target string in more than one place then preceding it with .* forces it to
match the last occurrence. Without that it matches the first occurrence.

Rob