Switch (module) and mod_perl problem.

[John Day <jo...@wordsnimages.com>]

In my never ending search for more elegant looking and self-documenting code I decided to try out the Switch module. In the following fragment of code: 

#!/usr/local/bin/perl

# AppSys: Manage Profile

use strict;
use CGI qw/:standard/;
use CGI::Carp qw(fatalsToBrowser);
use Switch;

my $cgi = CGI->new;

my $control = 'Search';
switch ( $control ) {
    case ("Search") { 
        print $cgi->header;
        print $cgi->start_html;
        print $cgi->p("Search");
        print $cgi->end_html;
         }
}

produces the following in the Apache error log: 

[error] syntax error at /home/appsys/www/modperl/ap03.pl line 12, near ") {"
syntax error at /home/appsys/www/modperl/ap03.pl line 14, near "}
}"

When run as an Apache::Registry script. 

When run under mod_cgi (i.e. run from the cgi-bin directory on the same server, it works perfectly and prints 'Search' on the browser. 

Server is: RH8.0, Apache 1.3.28, mod_perl 1.28, Perl 5.8.1

John 

Re: Switch (module) and mod_perl problem.

[Steve Hay <st...@uk.radan.com>]

Geoffrey Young wrote:

>
>
> John Day wrote:
>
>> In my never ending search for more elegant looking and 
>> self-documenting code I decided to try out the Switch module. In the 
>> following fragment of code:
>> #!/usr/local/bin/perl
>>
>> # AppSys: Manage Profile
>>
>> use strict;
>> use CGI qw/:standard/;
>> use CGI::Carp qw(fatalsToBrowser);
>> use Switch;
>>
>> my $cgi = CGI->new;
>>
>> my $control = 'Search';
>> switch ( $control ) {
>>     case ("Search") {         print $cgi->header;
>>         print $cgi->start_html;
>>         print $cgi->p("Search");
>>         print $cgi->end_html;
>>          }
>> }
>>
>> produces the following in the Apache error log:
>> [error] syntax error at /home/appsys/www/modperl/ap03.pl line 12, 
>> near ") {"
>> syntax error at /home/appsys/www/modperl/ap03.pl line 14, near "}
>> }"
>>
>> When run as an Apache::Registry script. 
>
>
> Switch uses source filters, which probably doesn't work well with the 
> way Registry wraps scripts up into handler() subs.
>
> without getting too far into Filter::Util::Call, Switch.pm, or 
> Text::Balanced there is probably not much we can do to help. 

Indeed.  I've tried and failed to get source code filters working under 
Apache::Registry in the past, and I tried it again only recently with 
the same result -- it doesn't work.

However, it does work fine if you write mod_perl handler()'s yourself.

- Steve

Re: Switch (module) and mod_perl problem.

[Geoffrey Young <ge...@modperlcookbook.org>]

John Day wrote:
> In my never ending search for more elegant looking and self-documenting code I decided to try out the Switch module. In the following fragment of code: 
> 
> #!/usr/local/bin/perl
> 
> # AppSys: Manage Profile
> 
> use strict;
> use CGI qw/:standard/;
> use CGI::Carp qw(fatalsToBrowser);
> use Switch;
> 
> my $cgi = CGI->new;
> 
> my $control = 'Search';
> switch ( $control ) {
>     case ("Search") { 
>         print $cgi->header;
>         print $cgi->start_html;
>         print $cgi->p("Search");
>         print $cgi->end_html;
>          }
> }
> 
> produces the following in the Apache error log: 
> 
> [error] syntax error at /home/appsys/www/modperl/ap03.pl line 12, near ") {"
> syntax error at /home/appsys/www/modperl/ap03.pl line 14, near "}
> }"
> 
> When run as an Apache::Registry script. 

Switch uses source filters, which probably doesn't work well with the way 
Registry wraps scripts up into handler() subs.

without getting too far into Filter::Util::Call, Switch.pm, or 
Text::Balanced there is probably not much we can do to help.

you might be able to reduce the problem with a test case outside of mod_perl 
and pass it on to the appropriate people if it doesn't work.  Registry 
essentially does this

package Apache::ROOT::modperl::ap03_2epl;
 

sub handler { 

   # your script
}
1;

then calls Apache::ROOT::modperl::ap03_2epl::handler().

HTH

--Geoff

Re: Switch (module) and mod_perl problem.

[Perrin Harkins <pe...@elem.com>]

On Thu, 2003-10-30 at 11:41, Mark Hawkes wrote:
> At 11:23 2003-10-30 -0500, you wrote:
> >In my never ending search for more elegant looking and self-documenting 
> >code I decided to try out the Switch module.
> 
> I've sometimes faked a switch statement like this...

That's a good approach, and there are more examples in perlfaq7:
http://perldoc.com/perl5.8.0/pod/perlfaq7.html#How-do-I-create-a-switch-or-case-statement-

- Perrin

Re: Switch (module) and mod_perl problem.

[Mark Hawkes <ha...@onetel.net.uk>]

At 11:23 2003-10-30 -0500, you wrote:
>In my never ending search for more elegant looking and self-documenting 
>code I decided to try out the Switch module.

I've sometimes faked a switch statement like this...

SWITCH: {
   $foo eq 'r' && do {
     # read stuff
     last SWITCH;
   };
   $foo eq 'w' && do {
     # write stuff
     last SWITCH;
   };
   DEFAULT: {
     # default stuff
   }
}

Hopefully more portable than the Switch module? I admit it's less elegant 
though :-/

Mark