my(@conf);
if(defined($opt{config_file})){
   
   my($buf);
   $buf = `cat $opt{config_file}`;
   
   # slurp
   if (eval($buf)){
      print STDOUT "$me: Read config from $opt{config_file}\n" if $opt{verbose};
      }
   else{
      die "$me: Error reading config from $opt{config_file} (fix it!)\n\n";
      }
   }
else{
   @conf = @default_conf;
   }

##</code><code>##

$ cat 1174639.conf 
@conf = (
   {'step' => 8,  'blur_fwhm' => 4,  'iterations' => 20},
   {'step' => 6,  'blur_fwhm' => 3,  'iterations' => 20},
   {'step' => 4,  'blur_fwhm' => 2,  'iterations' => 10},
   {'step' => 2,  'blur_fwhm' => 1,  'iterations' => 10},
   ); 

##</code><code>##

$ cat 1174639.pl
use strict; use warnings; use feature 'say';
use Data::Dumper;

my $file = '1174639.conf';
my $buf = `cat $file`;
my @conf;
eval( $buf );
say Dumper \@conf;

##</code><code>##

$ perl 1174639.pl
$VAR1 = [
          {
            'blur_fwhm' => 4,
            'step' => 8,
            'iterations' => 20
          },
          {
            'step' => 6,
            'blur_fwhm' => 3,
            'iterations' => 20
          },
          {
            'blur_fwhm' => 2,
            'step' => 4,
            'iterations' => 10
          },
          {
            'blur_fwhm' => 1,
            'step' => 2,
            'iterations' => 10
          }
        ];