NAME

       Regexp::Common::URI::gopher -- Returns a pattern for gopher URIs.

SYNOPSIS

           use Regexp::Common qw /URI/;

           while (<>) {
               /$RE{URI}{gopher}/       and  print "Contains a gopher URI.\n";
           }

DESCRIPTION

   $RE{URI}{gopher}{-notab}
       Gopher URIs are poorly defined. Originally, RFC 1738 defined gopher URIs, but they were
       later redefined in an internet draft. One that was expired in June 1997.

       The internet draft for gopher URIs defines them as follows:

           "gopher:" "//" host [ ":" port ] "/" gopher-type selector
                               [ "%09" search [ "%09" gopherplus_string ]]

       Unfortunally, a selector is defined in such a way that characters may be escaped using the
       URI escape mechanism. This includes tabs, which escaped are %09. Hence, the syntax cannot
       distinguish between a URI that has both a selector and a search part, and an URI where the
       selector includes an escaped tab. (The text of the draft forbids tabs to be present in the
       selector though).

       $RE{URI}{gopher} follows the defined syntax. To disallow escaped tabs in the selector and
       search parts, use $RE{URI}{gopher}{-notab}.

       There are other differences between the text and the given syntax.  According to the text,
       selector strings cannot have tabs, linefeeds or carriage returns in them. The text also
       allows the entire gopher-path, (the part after the slash following the hostport) to be
       empty; if this is empty the slash may be omitted as well. However, this isn't reflected in
       the syntax.

       Under "{-keep}", the following are returned:

       $1  The entire URI.

       $2  The scheme.

       $3  The host (name or address).

       $4  The port (if any).

       $5  The "gopher-path", the part after the / following the host and port.

       $6  The gopher-type.

       $7  The selector. (When no "{-notab}" is used, this includes the search and
           gopherplus_string, including the separating escaped tabs).

       $8  The search, if given. (Only when "{-notab}" is given).

       $9  The gopherplus_string, if given. (Only when "{-notab}" is given).

       head1 REFERENCES

       [RFC 1738]
           Berners-Lee, Tim, Masinter, L., McCahill, M.: Uniform Resource Locators (URL).
           December 1994.

       [RFC 1808]
           Fielding, R.: Relative Uniform Resource Locators (URL). June 1995.

       [GOPHER URL]
           Krishnan, Murali R., Casey, James: "A Gopher URL Format". Expired Internet draft
           draft-murali-url-gopher. December 1996.

SEE ALSO

       Regexp::Common::URI for other supported URIs.

AUTHOR

       Damian Conway (damian@conway.org)

MAINTAINANCE

       This package is maintained by Abigail (regexp-common@abigail.be).

BUGS AND IRRITATIONS

       Bound to be plenty.

LICENSE and COPYRIGHT

       This software is Copyright (c) 2001 - 2009, Damian Conway and Abigail.

       This module is free software, and maybe used under any of the following licenses:

        1) The Perl Artistic License.     See the file COPYRIGHT.AL.
        2) The Perl Artistic License 2.0. See the file COPYRIGHT.AL2.
        3) The BSD Licence.               See the file COPYRIGHT.BSD.
        4) The MIT Licence.               See the file COPYRIGHT.MIT.