Well there are some good explainations here but I'm not sure anyone got at your core question. Which is "What type of data structure does HTML::Template take?"

At the most basic level HTML::Template takes a hash. If you have a hash of key value pairs that all appear in the template then you can simply pass it the param call the hash and it will work.

The <tmpl_loop> structure takes a reference to an array of hash references. And you can have loops inside your loops.

So here's how you can make @data into @loop_data, I'm going to avoid using map so that you can get a clearer idea of where the data is going:

my @loop_data = ();
foreach my $array_ref(@data) {
     my @inner_loop = ();
     foreach my $element (@$array_ref) {
          push(@inner_loop,{var1=>$element});
     }
     push(@loop_data,{loop2=>\@inner_loop});
}
[download]

Hope that helps... I'm going to post this and the try to write some code that does it with map I can't think of it off the top of my head right now.

***UPDATE***
Here's some code to do it with map

my @loop_data = map { {loop2=> [map { {var1=>$_ } } @$_ ] } } @data;
[download]

***UPDATE 2 ***
Fixed the bug. :) thanks fireartist

Chris

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