[squid-users] correct regular expression to use to capture all

[Alex Rousskov]

On 7/8/23 06:14, Stuart Henderson wrote:
> On 2023-07-07, robert k Wild <robertkwild at gmail.com> wrote:
>> --===============6398075081121841451==
>> Content-Type: multipart/alternative; boundary="000000000000a03dcc05ffeb4428"
>>
>> --000000000000a03dcc05ffeb4428
>> Content-Type: text/plain; charset="UTF-8"
>>
>> hi all,
>>
>> i know ive been talking about this before but i want to understand why i
>> cant use this regex
>>
>> (^|.*)redshift3d.com$
> 
> this matches anythingredshift3d[any single character or nothing]com

Correction: A regular expression "." does _not_ match "nothing" (i.e. 
zero characters).

In some contexts, "." may not even match some special single characters, 
but those contexts are probably not applicable to this thread scope.


>> instead i have to use this
>>
>> (^|\.)redshift3d.com$ OR
> 
> this matches redshift3d[any single character or nothing]com
> or anything.redshift3d[any single character or nothing]com

... or .redshift3d.com

Same "nothing" correction here.


>> (^|\.)redshift3d\.com$
> 
> this only matches redshift3d.com or anything.redshift3d.com

... or .redshift3d.com


Alex.


> So, if you only want to match on things exactly in the redshift3d.com
> domain and no others, you need the last one.