I think you want an Array of Arrays (AoA). Read about them in perldsc and perlref.

YuckFoo

Here is one way to go:

#!/usr/bin/perl

  use strict;
  use Data::Dumper;

  my @parts = ([]);

  while (my $line = <DATA>) {
    chomp $line;
    if ($line =~ /^\d-\d\d-ABC\d\d/) {
      push (@parts, []);
    }
    push (@{$parts[-1]}, $line)
  }

  print Dumper \@parts;

__DATA__
1-11-ABC22 (12:12)   ABC 12 Foo Bar Foo Bar
Foo Bar Foo Bar

2-15-ABC33 (12:12)   ABC 12 Foo Bar Foo Bar
Foo Bar Foo Bar
--
1-11-ABC33 (12:12)   ABC 12 Foo Bar Foo Bar
Foo bar Foo Bar
--
1-11-ABC33 (12:12)   ABC 12 Foo Bar Foo Bar
Foo abr Foo bar
Foo Bar
Foo Bar
Foo Bar
--
2-15-ABC45 (12:12)   ABC 12 Foo Bar Foo Bar
Foo Bar Foo Bar

3-33-ABC15 (12:12)   ABC 12 Foo Bar Foo Bar
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