Split your regex in two: 
use strict;
use warnings;
use Data::Dumper;

my $key;
my %data;


while (<DATA>)
{
    $key = $1, next        if /^CALCON\((\w+)\)/;
    $data{$key}->{$1} = $2 if /^\s+(\w+)\(([\w\d\s]+)\)/;
}

print Dumper (\%data);

    

__DATA__
CALCON(test1)
{
  TYPE(U8)
  FEATURE(DCOM)
  NAM(stmin)
  LABEL(Min seperation time between CFs)
  MIN(0)
  MAX(127)
  UNITS(ms)  
}

CALCON(test2)
{
  TYPE(U16)
  FEATURE(DCOM)
  NAM(dcomc_sestmr_timeout)
  LABEL(DCOM Session Timer Timeout)
  MIN(0)
  MAX(65535)
  UNITS(ms)
}

[download]
Output: 
$VAR1 = {
          'test1' => {
                       'MIN' => '0',
                       'UNITS' => 'ms',
                       'FEATURE' => 'DCOM',
                       'NAM' => 'stmin',
                       'MAX' => '127',
                       'TYPE' => 'U8'
                     },
          'test2' => {
                       'MIN' => '0',
                       'UNITS' => 'ms',
                       'FEATURE' => 'DCOM',
                       'NAM' => 'dcomc_sestmr_timeout',
                       'MAX' => '65535',
                       'TYPE' => 'U16'
                     }
        };

[download]


holli, /regexed monk/

In reply to Re: nested reg ex over multiple lines by holli
in thread nested reg ex over multiple lines by eg8rds

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