PCRE named captures sill counted in numerical variables list

Server NGINX
1

I tried to configure the following location with something like:

location ~*
“^/([[:alpha:]]{1,8}(?-[[:alpha:]]{1,8})?)(/.*[^/])?/?$” {
try_files $uri $uri/ $2/?lang=$1&$args;
}

​However, the $2 variable does not catch the last part of the URI as
expected (either it catches the named capture or nothing at all, that I
do
not know nor care).​

​Using $3 instead of $2 does the job.​

​I thought that using named captures allowed for those capture not to be
counted in numerical variable​
​.

​
​Am I wrong expecting that?

B. R.

2

​Thanks Maxim,

I just understood my mistake: I was confusing (once again, I think)
named
captures and subpatterns…

What I wanted to use was the OR logic capability of captures while
actually
not capturing them…
The starting question mark of both syntax confused me…

If anyone is intereted in it, the intended (and working) syntax is:
location ~* “^/([[:alpha:]]{1,8}(?:-[[:alpha:]]{1,8})?)(/.*[^/])?/?$” {
try_files $uri $uri/ $2/?lang=$1&$args;
}

Working on multi-language URIs on webserver-side… ;o)

B. R.

3

Hello!

On Thu, Apr 03, 2014 at 03:08:14PM +0200, B.R. wrote:

​Using $3 instead of $2 does the job.​

​I thought that using named captures allowed for those capture not to be
counted in numerical variable​
​.

​
​Am I wrong expecting that?

Yes, you are wrong, “man perlre” says:

   Named groups count in absolute and relative
   numbering, and so can also be referred to by those numbers.

The same does “man pcrepattern”:

   Named  capturing parentheses are still allocated numbers
   as well as names, exactly as if the names were not  present.

From pattern point of view, it’s just an human-friendly alias for
a capture.

–
Maxim D.
http://nginx.org/