in reply to CGI::Application - alternative to using $self->param?

After you create the C::A instance, you can always stick it in a global variable: 
my $cgi = new CGI::Applicaton(...);
$::global_var = $cgi;
... use $::global_var now anywhere ...

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A variable like $::global_var is a fully-qualified name which is as close as Perl gets to global variables. It is equivalent to $main::global_var or to using our in package main: 

...
{
  package main;
  our $global_var; # same as $::global_var and $main::global_var
  ...
}

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You can create a tie interface if you want to access parameters like you did with a hash. See man perltie for more details. However, if you are writing new CGI applications, I wouldn't do this. Just extract parameters into simple variables if you need to use them more than once. A tie interface would allow you to use hash-like syntax for the following operations: 

print $hash{'key'}    # same as print $webapp->param('key')
$hash{'key'} = 3;     # same as $webapp->param('key', 3);

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However, I would make sure it is really worth implementing because it will add complexity and degrade your application performance.

If you really need to access the values as a hash, perhaps you can first extract all the CGI parameters to a hash like this: 

our %hash;
my @all_params = $webapp->param();
for my $p (@all_params) {
  $hash{$p} = $webapp->param($p); #
}
... use %hash instead of calling $webapp->param(...) ...

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Re^2: CGI::Application - alternative to using $self->param?
by friedo (Prior) on Nov 21, 2007 at 00:20 UTC
    Also, the ->param(...) method is read-only - you can't change values of parameters with it.

    Sure you can. It works pretty much just like CGI's param method. This works fine:

    $self->param( key => \%valuahash );

    If you want a hash with all your params, you can get it like this:

    sub some_run_mode { 
    my $self = shift;
    # note that CGI.pm does the same thing:
    my @params = $self->param; 
    my %hash = map { $_ => $self->param( $_ ) } @params;
}

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    That would be a little tedious to do in every runmode, but you could do it in a prerun hook instead.

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[d/l]
[select]
      Thanks for pointing that out. Shortly after writing that I decided to check it out and re-edited my response accordingly.
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