Re: Accessing variable hash elements

So, I ended up writing a little modifier, because the case changed slightly. 

I want to use $variable to access a hash element such as:
$hash->{$variable}
*** and ***
$hash->{$variable}->{'value'}

So I wrote the following Modifier called lookup:  
$Petal::Hash::MODIFIERS->{'lookup:'} = sub {
    my $hash = shift;   
    my $args = shift;     
    my @args = split(/\s+/, $args);
    ##the first is the hash name
    my $the_hash = $hash->fetch ($args[0]);
    my $param    = $hash->fetch ($args[1]);
    if($args[2])        
    {                       
        return $the_hash->{$param}->{$args[2]};
    }
    else
    {
        return $the_hash->{$param};
    }
};
This is used in the code like:

<span tal:replace="lookup: the_hash variable field_name">replace me</span>

and it works nicely

I know I have no real validation built in yet, but that aside, any comments?

Regards

Simon


  ----- Original Message ----- 
  From: [email protected] 
  To: Petal Mailing List 
  Sent: Friday, April 29, 2005 1:38 PM
  Subject: [Petal] Accessing variable hash elements


  Ok, I know this must be a stupid question, I probably just need more caffeine but.....

  I need to access a variable hash element $user{$group}

  if I have a Hash as : 
  my %user = ( name => 'Simon', group1 => '1', group3 => '1') ;

  and an array like :
  my @groups = (qw/group1 group2 group3/ );

  and I want to do:

  <td tal:repeat="group groups">
      <span tal:content="user group">is the user in the group</span>
  </td>

  I know this last bit is incorrect, but there must be a simple way of accessing $user{$group}

  Thanks

  Simon