I have a regexp::grammar set of rules to read a parameter files, quite complex ones. I got the matching alright, but I fail in simplifying the result structure.
Instead of the rule's name, I'd much prefer to see the name field as hash key, then simplifying the whole thing to something like this (I want to keep the arrays since the values can actually be lists):
The data looks like this, elements grouped in { }, that can be arbitrarily nested. The values to the tokens can be scalars or lists

...
      <ParamMap."HARDWARE">
      {
        <ParamBool."MagnitudeImages">  { "true" "false" "true" }
        <ParamString."ProtectedSize">  { "350"  }
      }
...
[download]

The (simplified) code looks like this:

        my $g=qr{
        <nocontext:>
        <protocol>
<rule: protocol> <[MATCH=element]>+ <minimize:> 
<rule: element> ( <MATCH=map> | <MATCH=p_str> | <MATCH=p_bool> ) #<min
+imize:>
<rule: map> \<  ParamMap  \. <name> > \{ <[element]>* \}
<rule: p_str>  \< ParamString \. <name> > \{
         ( <[string]>* )?
\}
<rule: p_bool>  \< ParamBool \. <name> > \{ 
        #<debug: on>
         ( <[bool]>* )?
\}
<rule: string> <_qq> <[MATCH=literal]>* <_qq>
<token: literal> [.'!\w_@\+\-\(\)\(\)\#{}\\\[\]]+ 
<token: _qq> \"
<token: name>  <_qq>\w*<_qq>
<rule: bool>  <_qq><MATCH=(true|false)><_qq>    
}xms;
[download]

My desired results would be something like that:

$VAR1={
'HARDWARE'=>[
    'PhaseImages'=>[ true, false, true ]
    'RoFOV'=>[ '230.0000000000000000', ]
]
}
...
[download]

so far I get this:

$VAR1 = {
          'protocol' => [
                          {
                            'name' => '"HARDWARE"',
                            'element' => [
                                           {
                                             'bool' => [
                                                         'true',
                                                         'false',
                                                         'true'
                                                       ],
                                          name' => '"MagnitudeImages"'
                                           },
                                           {
                                          'name' => '"ProtectedSize"',
                                             'string' => [
                                                           [
                                                             '350'
                                                           ]
                                                         ]
                                           }
                                         ]
                          }
                        ]
        };
[download]

My sincere apologies for the bad formating.