My approach when parsing lists depends on the nature of the list.

If I can find out from looking at a single line what kind it is, then I use regular expressions to fill out a hash and flush the record whenever a new set starts.

If I can't find out from looking at a single line what kind it is, I use counters or flags to know what line I am on.

In your case, it looks to me as if you basically have a report with some header data and then three payload lines, the issuance date, the address and the description. One ugly thing seems to be that the address and the permission can span multiple lines, but from the unrepresentative example you have posted, each item seems to be delimited by a blank line from the previous item.

Going from these assumptions, my approach would be something like the following (untested):

#!perl -w
use strict;
use Data::Dumper;

# Output a row of information
sub flush {
    my( $record ) = @_;
    if( $record->{permit} ) {
        print Dumper $record;
    };
    delete $record->{permit};
};



# This will collect all information for one entry:
my %info;
my $last_page;
my $expected_pages;
my $record_kind;

my %next_record = (
    address => 'description',
    description => undef,
);

while(<DATA>) {
    if( m!^Page (\d+) of (\d+)! ) {
        $last_page = $1;
        $expected_pages ||= $2;
        next;
    };
    if( m!^(Jan|Feb|...|Jun|...) (19\d\d|20\d\d)! ) {
        $info{ report_date } = "$2-$1";
        next;
    };

    # ... more code to skip the header left for the reader
    next if( m!MONTHLY EXTERNAL MODIFICATIONS PERMITS REPORT! );
    next if( m!^Permit Issued! );

    if( m!^(\d\d)/(\d\d)/((?:19|20)\d\d)$! ) {
        flush(\%info);
        $info{ permit } = "$3-$2-$1";
        $record_kind = 'address';
        <>; # skip empty line
        next
    };

    # Fast-forward until the next set of lines
    if( $record_kind ) {
        while( <> !~ /^\s*$/ ) {
            s!\s*$!!;
            $info{ $record_kind } .= " " . $_;
        };
        $record_kind = $next_record{ $record_kind };
    } else {
        die "Unknown line [$_] on line $.";
    };
};

warn "Uhoh - expected $expected_pages but only read up to $last_page"
    if( $expected_pages != $last_page );

__DATA__
Page 1 of 3

100 Civic Center Way
Calabasas, California 91302

7/12/2012 9:21:02AM

MONTHLY EXTERNAL MODIFICATIONS PERMITS REPORT
Jun 2012

Permit Issued

Address

Description

06/01/2012

26166 ROYMOR
DR

Upgrade panel from 100 amp to 200 amp

06/04/2012

24956 NORMANS
WAY

(6) light fixtures @ patio; (3) branch circuits; (4) electric
heaters

06/05/2012

4273 VICASA
DR

Construct 339 SF Covered Loggia

[download]

In reply to Re: creating array of hashes from input file by Corion
in thread creating array of hashes from input file by chimiXchanga

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